input on big block mounts

[rc999]

need some info on using perf. on line tubular mounts or oem big block tower. Does the engine sit higher with stock mounts? if the engine sits lower are there clearence issues with header? I have a 67 gmc original 6cyl that some one put a small block in. Will the small block mounts work on the big block?thanks for any help

[RSRXION]

I just finished the install of a 454 in my 72. I used the 73-87 style mounts completely. I did not use any portion of the original 72 small block mounts. They almost lined up with the frame holes and required only a slight amount of bolt hole reaming to get them bolted in. One of the holes lined up perfectly and that made it very easy to locate the others. The trans was also converted to a TH-400 and the 76 crossmember bolted right into the 72 chassis with existing holes. Since my truck was originally a small block I can't testify as to whether or not the engine sits too high. Everything seems to line up . I'll install the shroud this weekend and I'll know better then. Here's a few pics. Dean