66CLEETUS

Hello to anyone out there, I'm not sure if I'm using this web site correctly. I have just purchased a 1966 Bel Aire 2 dr. that had an L6 motor with a 2-speed power glide transmission. I have the frame off and have painted the frame, installed all lower control arm bushings - front and rear, but before reinstalling the lower control arm on the front I need some insight as to the motor mounts I wish to put a 350 or 327 engine in this car, and the mounts look to me as though they need to be put in before the control arms are put back in, other wise you can't reach the bolts on the bottom side of the frame. Are the engine mounts different for a V8 than they are for the 6cyl. There are two sets of holes for the mounts on the cross member, one set lower and a set that is higher. The mounts that came off were on the lower set of holes(I'm assuming this was for the 6 cyl. are the upper set for a V8 or for a big block motor? And where can I find the mounts that I need for a V8. This is my very first project and there's alot I don't know.Can anyone help me? Thank You.