Need help with speaker wire connection to ARC Classic 60

A) Bend the fins down enough to fit a spade.
B) Bend/trim the spade enough to fit between the fins.
C) Both

I wouldn’t bend trim or modify your Classic 60 or you’ll just hurt it’s value. If you don’t have the skills, no disrespect, have Chris at VH Audio or someone else make you some jumpers so you can use other heavier cables. Cardas, Audio Quest and others make spades that work just fine on your amp. The dividers/fins are plastic I recall so they’re not going to bend easily and again it’s a classic amp and I wouldn’t mess it up.

I have no desire to modify the amp.  I ordered some Kimber Kable 8tc in bi-wire configuration with bananas on the speaker end and bare wire on the amp end so I can terminate once I found the right solution. 
One thought I had was to bend the wire in a hook and solder, but I’m not sure how good of an electrical connection that would provide.

Those fins will most likely just snap off if your not careful. That is called a barrier type terminal strip. Your lucky to have them, AR knows what they are doing. Your best connection is going to be with good quality ring lugs carefully crimped onto your speaker wires. Tighten the screws holding the ring lugs snuggly and never ever worry about your speaker connections at that end of the cable. If your lucky, your speakers support the same type of connectors as well.
Banana type connections are designed for temporary connections in test gear and how they wound up in stereo gear is a mystery to me. They suck! they fall out or can be easily pulled out, sometimes shorting the amplifiers outputs on SS gear costing major dollar repairs.
When using an amp with 5 way binding post I never use banana jacks, either bare tinned wire or a crimp on connector.
Did I say yet that banana plugs suck? Yes, they suck! Get rid of them.

BillWojo

This is what you need:

https://www.amazon.com/Hi-end-Adapter-Speaker-Connector-Wy-yp01/dp/B00X9FET7I/ref=pd_sbs_23_img_0/13...

Why would you put those on barrier strip connectors, just to use banana jacks? Did you ever look at a banana jack closely? They make several small point contacts inside of the hole, surrounded by open space so that things can slowly oxidize. They were never intended for long term connections, they are for quick and dirty test instrumentation connections and just the process of inserting and removing the banana jack helps clean off the oxidation each time it's set up. They were never intended for set it and forget it applications.
A ring lug on a screw type terminal forms a gas tight seal when tightened and is forever.
There are many 50 or 60 year old industrial controls with hundreds of wires secured by ring lugs and screws. In all my years as a tech, the only failure I have seen is if the screw was never tightened. If it's a high voltage/amperage circuit it fails almost immediately, on low voltage control circuitry it can take years before oxidation takes it's toll and the circuit fails.
I have never seen so much misinformation as in audio. Bling seems to outweigh good engineering all the time. Yet folks will pay thousands of dollars for a piece of gear (superbly engineered and built) and use junk connectors to hook it into their system. Really amazes me.
BillWojo

I had the same issue when I owned an ARC D70Mk2...which was a truly great amp. The solution for me was to have the speaker cable company add small spades at the amp end ( most can do this with no problem).
Do NOT snap off the fins or try and bend them...bad advice above!! 

Why would you put those on barrier strip connectors, just to use banana jacks?

It accept bare tinned wire as well.

https://images-na.ssl-images-amazon.com/images/I/51phA0WYkaL._AC_SL1280_.jpg

There are many 50 or 60 year old industrial controls with hundreds of wires secured by ring lugs and screws. In all my years as a tech, the only failure I have seen is if the screw was never tightened. If it’s a high voltage/amperage circuit it fails almost immediately, on low voltage control circuitry it can take years before oxidation takes it’s toll and the circuit fails.
I have never seen so much misinformation as in audio. Bling seems to outweigh good engineering all the time. Yet folks will pay thousands of dollars for a piece of gear (superbly engineered and built) and use junk connectors to hook it into their system. Really amazes me.

@BillWojo, calm down my friend, I were a tech working at Toshiba Singapore 40 years ago.

imhififan +1

I’ve been using what inhifiman suggested with banana plugs in my old McIntosh amplifier for several years with no issues. I do remove them every now and then and clean them with alcohol just to keep the contacts clean. They work very well.

Surely there's some Vandersteen technology that's transferrable to this case.

So over the years I’ve used the banana connector adapters recommended by inhifiman and kalili on the following amplifiers with great success: McIntosh MC30, Audio Research D-40, D-70, D-115B, Classic 30 and Classic 60. The speaker wires used were either factory terminated Audioquest or Kimber Kable. Zero issues in terms of poor connection, banana connector falling out, shorts, oxidation, end of the world, etc.

 

As already suggested as well, do not try and bend or modify the barrier strips. They can/do break easily.

So I ended up just crimping on hoops and soldering.  Nothing fancy or gold plated, but they are nice and secure.

(((A ring lug on a screw-type terminal forms a gas-tight seal when tightened and is forever. )) Agree with above Vandersteen technology eyelets work great
Longer chassis screws and collets can work and are easily reversible.Have you ever done the experiment or comparison with big metal connectors or too many adapters plumed together? It sucks and sounds worse than simple collet extensions and longer screws that escape the height of plastic fins.also sticking the banana into a threaded hole sucks as well becomes a diode mess.
 Best JohnnyR