All of my stuff is GMC so in my case that's not an issue. All mine is '54 or '55 1st too, so it should all be at least close.
The truth though is that I'd be much more likely to adapt a modern automatic than to perform this conversion. I think it would both be less work and would give a better result.
Plus I just found a '53 GMC with a Hydra-Matic and am sure tempted by a first year Hydra-Matic even though I really have no business even thinking about buying another truck right now.
