John
dont hold me to this as this advice is 50/50.....the trans bracket should be the same and the drives shaft may be smaller...not sure on the yoke on the shaft to go from C4 to FMX...never done it. A test fit should answer your question but someone may have done this that can answer that question
as for the 6 banger engine brackets.....going from 6 to V8 all 64-70 require a different bracket and if your going FE or Big block in 67-70 require another bracket all together from a small block
Easiest way to answer your question is go on ebay USA and type in 72 V8 engine brackets and see what you get...if they pop up...you know you need em
Matt
PS....sorry mate, 71 onwards is talkin dutch to me...dont really dabble with them
