How many cubic feet? Best guess something on the order of 250-400 cubic feet.
Mind you not all of that is junk in the classic sense. Much of that is what I'd call
I use 50 drawer bins and some with larger drawers that are only 18 drawers in the same
overall size. There are 8 of those for just routine stuff like screws, resistors, caps, diodes,
connectors, LEDs, common transistors, and so on. ITs part of the non-junk part. Tackle boxes
are not space efficient. However there are maybe 12 of the variable pocket size clear
polyethylene boxes of varying heights for things like batteries, electrolytic caps, crystals,
small relays and the like.
Junk aka random assemblies, chassis and boards, mechanical, cable and wire
are in large tubs maybe of the 30 gallon size. FIgure 10 of those. Plus another 15
printer paper boxes (10 ream size) many are marked as to content.
Its organized so the two car garage can hold two cars, and a workbench there
for messy activities, even after 35 years.
The running joke with friends is, I likely have unobtainium.
Regarding the X1M info I have that and its good but cannot be used directly
with BITX as it was designed based on the MC1350 IF chip. That would be
tough to shoe horn into the BITX design. The basic idea is worth understanding
and with some changes could be applied would be very useful.