OK, here goes...
I had to split it into two boards.
I'm hopeful if you lay the caps and transistors down you will be able to fit them both into a 125B. I would place the modulation board 1st, then the main board on top, with a playing card in between. If ticking is a problem, you may need to put a shield between the two boards, which is fairly easy to do. Let me know if needed.
The boards are connected together at points A,B,C and D.
Note, the ICs on the main board are upside down. I also tried to place the caps so you could lay them down.
Hope you pull this one off!
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1978 Gibson Les Paul Standard, Cherry Sunburst