Questions on capacitor replacement

There are a few things to consider. First off, assuming that your soldering/de-soldering skills are good, the circuit board arrangement is important to consider. What I mean here is that in some cases, circuit boards can be stacked, one on top of another in the chassis. If I were to see this, I would put the top back on and call it quits.......... If there is easy access to the components that need replacing, that is the best situation, since the circuit board may not have to be removed at all........ Using Alcohol to clean the pots and switches is Not a good idea. There are products made specifically for this. I am not against the 'idea' of blowing dust out of a component, but realize that the very dust being blown around can possibly enter the pots ans switches that you are concerned about in the first place.......... One thing that is so important, is to take accurate, in focus, and useful photos of every section of the circuit, and layout from different positions so that you will have a good reference to how everything should go back together............
 I am sorry, but i don't have a suggestion for a reputable place to send this amp in S. Cal. Though it is a good idea not to ship any further than you have to, shipping to a QUALIFIED service center is of the utmost importance. Get references from those that know the difference. By this, ignore the folks who tell you that the people were nice on the phone, or were really fast, or cheap, etc. Hopefully, you get the picture.

It’s an easy DIY project, if you know how to solder, and have the right solder tips for it. :)

Make sure you don’t increase the uF too much in power supply caps, but DO get higher temp caps for the main and DO get equal or greater V ratings.

Increasing the uF too much stresses the transformer. Higher temp caps are longer lasting, and making sure you have at least the original V rating will prevent failure.

This one? https://www.hifishock.org/gallery/electronics/musical-fidelity/integrated-amplifier/a300-1-musical-f...Looks a good DIY to me.

Clean it up, sure - but vacuum and brush, not blast. 

What I will now explain is so simple I myself did it years ago back when I knew next to nothing, and it turned out to be the most cost-effective upgrade ever. Nothing beats parts upgrades like this. Nothing. You have to do it to hear for yourself. 

The four big black D-battery size things are power supply caps. There's a whole bunch of smaller caps all over the place. Caps have their values written right on them. Make a list. Then go on line and start looking them up. Make another list. 

You will quickly find there's lots of choices. Lots of specialty caps. You can go crazy or you can be sensible. Sensible to me means you have some ballpark budget and buy only the caps that fit that budget. 

Pay attention though because another thing you will quickly learn is the better caps almost always wind up being quite a bit bigger. Physically getting them to fit might not be worth the trouble. So there's that to consider too. 

Notice soldered to the boards in front of the big caps are 4 black things sticking up? Those are rectifier diodes. Newer/better/faster diodes will make a world of difference. My very first mod ever was a HEXFRED rectifier diode upgrade on my Aronov integrated amp. Deeper stage, liquid extension, blacker background. Could not believe. Best $8 I ever spent.  But again, they have to fit. Had to bend the heat sinks on the new ones to get them to fit. Don't look pretty. Sounds beautiful though. 

That's about it. Yes it really is that simple. Of course you can make it as hard as you want it to be. Or easy. You can also just clean it up, spritz a drop of lube on the volume knob, admire how good it still is after all these years, and screw the cover back on. Hard to go wrong either way.

Can you recommend anyone in the Central or Southern California area that knows what they’re doing?

Peter Noerbaek, the proprietor of PBN Audio, did a stellar job in reburbishing my discontinued English-made monoblocks. He’s outside San Diego.

Brooks Berdan in Monrovia, the tech there is great. 

@tomic601 I’m embarrassed to admit I used to live down the street from Brooks Berdan and never managed to even go in for a look. Of course at the time I don’t think I could have afforded anything there, but still I consider it a missed opportunity. I’ll need to contact them and see what service might cost me. Next time I was visiting the area I had intended to go there to hear some Spendor speakers and Rogue preamps anyway.
Then I’ll need to decide between spending time refining my soldering skills (and buying the right tools) or money to have it expertly done. @millercarbon that’s the one right down to the silver knob (instead of the gaudy gold one). Looks like a roomy layout. I have heard that though the older MF had a good rep overall they didn’t necessarily use the Uber premium parts. So theoretically it could end up better than new. Thanks for the comments everybody. 

The name of the tech at Brooks Berdan Ltd. is Tom Carione, and he’s in the shop on Wednesdays and Saturdays (his full time job is as a maintenance tech at a Los Angeles radio or TV (can’t remember which) station. Very knowledgeable, heck of a nice guy, charges reasonably.

Tom is an Ace !!!! Hyper efficient, great techs have a very organized and well thought out bench and hopefully a good ear as well. Tom is all that

There is great tech in San Diego also, works out of his house at a very competitive rate, has a pair of ESS monitors to check Sonics :-)  Mike Zuccaro - The Audio Craftsman