Actually I dont think any of the Panzers or Lees or Stuarts or the WWII British tanks he has would ever be used - they dont have live barrels - that also applies to all the German WWII artillery he had as well
The only real WWII or Korea tanks he has that have live barrels are a couple of Shermans that the Israelis extensively modified (so much so that they successfully were being used as tanks well into the 1980's) and one M47 tank
the APC's and half tracks are a different issue - all you need to arm them is a 50 caliber machine gun and they are ready to rock - including that M113 he has (and got to love that M113 fire support vehicle as well)
looked thru what he had that actually worked and was ready to go and what could be made ready to go that had live barrels or didnt need a main gun working to be effective (for instance the Ferret armored car that only has a 50 cal machine gun for its armament)
- six assorted armored cars,
- five tanks (a Conqueror Heavy tank, a Centurion Mk13 tank, two ex-Israeli Sherman tanks and a Patton M47 tank)
- M113A1 FSV
- six assorted armored personnel carriers
- a FV433 Abbot M105 SPG, a Sexton SPG armed with a 105mm howitzer and an M37 105mm Howitzer Motor Carriage
- three assorted recovery vehicles
- Saracen Command Post vehicle
- Israeli BTR 40
Like I said the Lees, Stuarts, Cromwells, Panzers and other stuff are great to look at but with no main guns that work they are better off being left there - or having the tank bodies removed and turn them into mobile gun platforms - otherwise they are just very large machine gun platforms
so I agree that the majority of his collection will never be used - keep in mind we are talking about a large amount of vehicles that he had - that fact that 25 vehicles can be used sounds like a lot
but keep in mind we are talking about 15-20% or so of his overall collection
and his shop and those techs are the real prize
And as I said use it or not if you want in your campaign - but its hardly magic or a stretch to have that many of his vehicles be drafted into MilGov - especially not one using CEV's as tanks in CA
either way more than nuff said on this subject