Component Stacking Question

Stacking is usually done because of space considerations, at least in my case. But if I have to do it, I use a platform/bridge that I have a friend custom-make for me at little cost (usually around $50). Simple but effective. Personally, I would not stack an amp/preamp unless there was no other choice. I'm also a believer of cooling fans for amps in 'dense' installations.

Audioguy85 you don’t understand the OP’s question. The whole point is to optimize placement from cooling/airflow and interference perspectives, it’s not not about what is or isn’t possible. 

Then how do you explain how an integrated amp works? It's all in one chassis in even closer proximity to the low level preamp section, and seemingly sounds ok....I see absolutely no issue in stacking.

these two specific pieces:

I would put a 1" spacer in between them so the pre-amp rear vent could do it's job, then stack away.

Stacking the amp on top is the only way if you must stack. Better off putting each component on a separate shelf, with as much room in between as possible to reduce effects of EMI and restricting airflow. Typically, the power amp needs the most breathing space, followed by the preamp and then tertiary components. Remember, heat is the enemy of electronics. 

Temp is OK.

Weight, maybe. Is the preamp strong enough for the weight?

Noise - Power transformers can radiate a lot of EMF noise, which can be picked up by other equipment too close to it. You'll hear it as hum.

tough to get a better amp for the money and even better when parts are upgraded. Great little sleeper amps.
And yes, don’t stack them. Best to get a cheap shelf set. stable, cheap, etc.

Preamp might be decent too, have never seen a image of the guts of them. One model of preamp, from that series and company (inkel).. was good enough to the the base unit for the Adcom Gfp-1. Also sold under the sears brand, LXI.

these are both Korean inkel products. styled differently, in minor ways... and the amp is slightly modified.
http://audiopub.co.kr/wp-content/uploads/2018/01/T_adcom-gfp1.jpg

What mijostyn said!

You might get away with it by using a platform and footers between the pre and amp with emi + rfi rejection.

Rocky, amplifiers have large power supplies which can generate noise in a low level preamp particularly if it has a phono section. It is always best to keep power amps away from low level devices. 

Stacking an amp is a no no get a stand.

Why not just get some kind of stand?

audio advisor has some stands for around $100