A quick update to my situation. First, the local wrecking yard with a truck I've been getting a few parts from allowed me to remove the crossmember that my truck is missing. I had to use a battery powered reciprocating saw and hand tools (no grinders allowed) but I was able to get the crossmember removed (the transmission was already gone which made things easier to access). So that takes all of the guess work out of how my motor and trans will sit in the frame. Second, I took a long look at the intake/exhaust manifold from the junk truck's 216. I showed it to my son and he agreed that there is no slope to the intake manifold (unlike the one on my cracked 250 which has an obvious slope). Then I saw what I have been missing all this time. The base where the carburetor mounts is machined at an angle! I never saw that on my motor because the Bakelite carb riser was in place (and the hole was stuffed full of paper towels to keep dirt/debris out). I'm not going crazy and everything is now right with the world! Thanks again to everyone for your input.
