What wheels for RC10 Goldpan

[Spoolio]

Got myself some JConcepts 5 spoke wheels for the RC10 but would like another set "just in case". Just in case of what I am not sure but better to be safe than sorry.

I know B4 rims are OK on the front so thats all sorted, but will B4 rims fit on the back end? If not would B3 ones do?

If no joy I'll have to try to source another set of JConcepts ones from somewhere I guess.

I do still have the original 2 piece wheels but the tyres have gone rigid after nearly 20 years of non-use. I s'pose they'd be good for drifting though .