The 383, 440 cast and steel crank models, and the hemi all got the same 4spd bell housing in 1970, it would be the 10.5" aluminum bell (not the 11" cast), same for (hp and hp2 440's, N, R, U and V code), this is the same for B and E bodies... I would confirm this with brewers..
The R code would obviously have the 8 bolt flywheel, while the U and V could would have an externally balanced 130 tooth 10.5" 6 bolt flywheel, the L, N, T motors with cast cranks would all have the same size and count wheel but in a neutral balance.
The R and V code would get the 18 spline tranny (in 70 this would be the universal fit tranny with both front and back mounts), while all others would have the 21 spline clutch and 833...
So if your friend wants to stay correct, he needs a bell housing and the U/V code flywheel... If he wants to just make his 11" work, he can call brewers and get the parts to do so, but 70 would not have a cast bell housing..
Obviously this is just me talking, not in the business of mopar trannys just conveying what I think to be true, I would call brewers to be 100% positive... good luck..
PS 1 more note, the v-code motor will have its own harmonic balancer on the front, it will have a weight attached to it, similar to the look of the cast balancers, BUT NOT THE SAME as that or the 4bbl HP carb,, its v code only balancer...
