no
using a block of wood to protect the oil pan, lift the engine with a jack to take the load off the mounts while changing them
yes, there is plenty of room for it, you will just have to change motor mounts if your car is a V6.
NO. Not even close.
small block and big block motor mounts are the same, so you should be able to take V8 motor mounts from most any Chevy engine bay.
the big block will bolt right to the small block motor mounts but they do make big block motor mounts that you can buy and install on the 66, it lets the engine sit a little lower and further to the drivers side.
yes you should have plenty of room in the engine bay. you probably will need to change the motor mounts and get a different tranny but other than that you should be fine.
big block to small block. you change the engine mounts position and possibly the trans. but yes.
I'm not sure why you'd want to put a small block Chevy in that Pontiac. But some things to keep in mind....most of the engine wiring is on the opposite side. You'll need to change engine mounts on the frame and you'll also have to make sure to get a Chevy transmission as the B.O.P.C trannys won't bolt to a Chevy.
Yes, a 283, 305, 307, 327 etc will fit. You should be able to use small block motor mounts from 1966
yes you can, you will just need the big block motor mounts to do it.
yes it can
I recently built a engine test stand for a 402ci Chevy engine. The distance between the motor mounts is 16 1/2 inches center to center. This should be true for small block and big block engines.