ur using the stock SBC mounts/perches right?
I tried that on my 65, I did get them in there but the motor sat too low IMO. You have to loosely bolt the top two bolts in and then ise a punch to line up the bottom hole. not a lot of fun. So I used the POL mounts but ECE has some that work well to.
This is what I used.
http://www.performanceonline.com/196...RACKETS-16820/