Here are some photos, schematic and others of ideas, projects or just fun stuff.

An idea is to make an ultrasmall amp built around and upon a chassis from an oscilloscope. This concentric assy would serve as input selector and gain control for an SRPP preamp based on the ECC85 or 2C51.
This is one method to mount discreet electronic components. Use a breadboard (with or without copper) and try to find a good way to mount it in your chassis. Connect the board to the valvesockets with good quality wires. I think this saves a lot of job (and fingertips).
This was the battlesight when I and my friend made up a second AML+ amplifier. The worst thing when working with your own made up project is the great amount of mechanical work.
For future "heavy" amplifiers I have two chassis of 4mm alu, that will carry a full stereos amp with ease.
I am about to build a 2AeSE in one and maybe a 12A6-PP in the second.

My GU50s and a Russian 807 (G-807).

A perfect material for invisible covering up holes - expanderd metal. The holes allows for fresh cooling air, som screening and keeps even the smallest fingers out: