This is posted on 1959-1979 Big Pontiac Tech also !! it is a good thread and maybe we can keep it going! i have a th400 that should be ready Mon or Tues. to install in my '64 Bonn! should be room in tunnel being i just had the leaky Jetaway jacked up 2" to remove mount and cross member for cleaning and (still had room to spare!) for possible cutting & welding and new paint! 50years of crud and oil it was pretty bad ! should have it by Tuesday evening i hope also with good news to post!! a friend has a '64 Gran Prix with a th400 in it and far as he knows there was no problem with install but said if there was the shop didn't tell him !!!
the Jetaway is 31 1/2" - the 400 (out of '74 Grandville)is 34 3/4" with the tail piece which is the 9" one. i like the idea of shorter drive line. have starter for block, new drive line to be made very soon! for those who may not know the early 60's b-bodies had two piece drive line short stub at rear end slips in to main tube and has a vulcanized rubber piece to hold them together! friend with a '62 cat had to have new made, the rubber broke free causing bad vibration.
dry run for drive line measurement late today ! new one to be made, 400 fit with great clearance (no beating on the tunnel)!! converter, fluid, starter ect. in AM will make adapter plate for cross member hookup to trans. to avoid cutting exhaust pipes to move C/M forward to much!
inspection cover on and new B&M kickdown switch working all is good !!! no slip no drips no errors!!!! what a big diff. compared to the jetaway!!! the 400 fit with no clearance issues except dip stick so went with flexible one !!!