Don't know if this is of any help or not, but I put a '55 235 into my 1940 GMC last year. I wrote up some lessons learned here:

http://oldgmctrucks.infopop.cc/eve/forums/a/tpc/f/462107036/m/4471020781

Steve


See my 1940 Canadian GMC:
http://community.webshots.com/user/ndnchf