Installing small block from the bottom

Best illustrative example I know of - Look at this thread showing HemiMark
and Donnie dropping the original 318 out of the bottom of Jim's Demon and
then dropping the /6 out of Mark's son's Duster sitting next to it. The Demon's
318 then goes into the Duster and a GenII Hemi goes into the Demon.
Notice that you don't even have to remove the hood to do it this way.

http://www.forabodiesonly.com/mopar/showthread.php?t=88358