We have a Sherman tank in the park here in London Ont. Although it is not a Sherman Vc Firefly, it should be the same. I scratched the paint on the undersurface of this tank, and it was green, right down to the bare metal. Try Hunnicut's book on the Sherman tank, as there are a number of pict's that might help here. This Sherman, in London Ontario, was from the !st Hussars, and was the only Sherman (early M4A1) with direct vision sights for driver/assistant driver, to survive the war intact from that outfit. Inside the tank, the surfaces are white, with red-oxide type primer in spots, but that is inside the beast. (One of the vision block covers is missing, and you can see inside the turrent and one sponson {right side})
This tank has been painted over and over again. Unfortunately, if the City of London doesn't look after it more, it will fall apart. It has a stress crack across the blocked off antenna port next to the hull .50 Cal. It is interesting to note that these British/Canadian tanks have a different colour than the American ones. More darker Olive green or Kakki Colour. I had to mix my paint in this mix;
7:1:1 with the 7 parts being Humbrol green (# 116) that came closest to British green,
one part Brown (matt dark) and one part White (for scale effect)
(To see a discussion about scale effect, read Tony Greenlands book on Panzer Modeling to see what I mean here ....)
This gives an approximate colour to the tank in the Park, and BTW the 1st Hussars Rgmt, looks after the painting of it each year, but the tank is City owned.
I have many hundreds of photo's of this tank, in Colour, and I am trying to figure out how to get them on the Net, for all to see.
Hope this helps some ....
Rob Savage