Hi,
My late father used to drive F class locos for London Transport. He always referred to them as "the big engines" and the E class as the "little engines".
When I was little he took me into Neasden (it was the late 1950s, can't imagine that happening nowadays!), and I couldn't see the difference. He pointed out the wheel arrangement, but as far as I remember body wise the only real difference was the F class had a bigger bunker, and seem to remember it stood higher - but I was only 9 at the time!,
There used to be a F class body shell kit available way back - GS models. I think it was RThompson of RT Models under a different guise but could be wrong.
SE Finescale also produce a kit, and as far as I can see the only real difference is the bunker - but don't know where they got the details from.
Jim Snowdon managed to "liberate" many of the old Met/LT drawings - which is how his Met Rolling Stock book came about. I wonder if he can help?
<edit> Have just phoned someone who should know (used to work with my father), and he has confirmed what I thought - they were identical except for bunkers, wheel arrangement and steam heating (F class wasn't used for passenger stock work - although he understood they were substituted for E class on occasions during WW2.
Forgot to mention I answered a similar question on another thread:
The F class, although very similar to the E, was in fact nearly 1ft longer (my dad who used to drive F class locos for LT, used to call them the "big engines" when comparing them to the E class - I won't say what he called the panniers when they arrived ). I think the difference might be because the F class had a larger coal bunker.
However the boilers and cylinders were the same as the later E class (the earlier E class cylinders were 0.5 in smaller than the later ones - definitely won't be noticeable in 2mm scale!).
Some basic dimensions:
Overall Length 33ft (over buffers)
Footplate width 8ft 5in
Driving wheels 5ft 6in (wheelbase 7ft 5in)
Bogie wheels 3ft 9.5 inch