The key to me with "experiments" like this is IF you are patient, persistent and will stick with it & work carefully and be willing to consider an experiment that didn't work a success in informing you what does and doesn't work. I've tried to maintain that mindset in my builds. To date, I've never cloned any production amp & I've probably tried over 2 dozen amp designs/prototypes. So, I consider a lot of my success in finding the tone I like to be from trial and error.
With respect and good will, Tubenit
I appreciate your thoughts here and I respect the experience they come from.
Overall, the whole thing is an experiment. If the reverb mod just becomes an exercise in brainstorming mods, and I wind up not doing it, that's OK.
At this point I'd like to keep exploring, and reserve judgement about whether to implement or not until later.
I think if I continue the planning process, work on the layout, make but do not isntall the "mini" turret board and circuit, and just set the reverb transformer on the chassis to see how much space there is, it will probably become more apparent as I go on whether this is a good idea or not. All I have to do is avoid doing anything that would be hard to undo later.
I made an attempt at a combined layout which I've attached.
Thoughts about the layout:
1) I'm new to all this, and modifying circuits adds a level of complexity - seeing how complex this was just to draw up, I'm a bit intimidated to actually try and do this.
2) Unless I'm just missing problems through inexperience, I'm guardedly optimistic about the amount of space available. A lot of the things I need are in the right places or nearby. Some of the connections on my layout are long, but that's mostly because the reverb board is off to the side. With the reverb board where I'd intend to put it, right next to the output transformer, all the things I need would be very close to one another
3) I made a bit of a mess by running all the grounds separately to the power ground star. If I were to do this, I'd be tempted to put a mini ground bus on the mini circuit board, and just send one wire from there to the power ground star.
The only "do it or don't do it" decision I'll have to make soon is whether I put a socket in the empty spot and include it in my heater wiring scheme.
My sense is that it would be harder to add it later than take it out later, so I'm tempted to go ahead and put it in for now.
One other thing that might or might not help: I was planning to make my own "mini" board, and given the small size of the components, I think I could make it pretty small.