Spitfire went to J-type with very last Mk4, I have a Couple of them.
TR6 went J-type with the CR cars, so 73. Same with Big Saloons, about 73 I think.
My 2 1850 3-rails boxes are WE ones, well one was, it has recently been rebuilt into a spare casing, so is now in a GR overstamped one, which show signs of being a WE before interestingly.