need a little help, 454/th350 fitment issue

[Marc33]

I just finished installing a freshly rebuilt 454 big block(73-79 truck block) in my 71 2wd 2500 long bed with the rebuilt oe th350. Truck came factory with a 350/350. I did install the correct big block uprights and the correct motor mounts as well as a new trans mount.

I added doug thorley 3o3 yc headers.

I have it all installed but the trans mount is about 1/2 inch too far back. I shifted the motor in the mounts all the way forward, too far forward in fact, now the drivers side header is hitting the lower control arm bolt. Still about 1/2 inch too far back.????????

I thought this all bolted up....what did I do wrong? the crossmember is mounted correctly i think.

Any help would be great. I want to get her running this weekend.

Thanks in advance for any help/direction.

[prostreetC-10]

Super simple.....just get the motor back where you want it or where it should be and drill some new holes through the frame and go! A trans crossmember is one of the easiest thing to install because it just sits there. Seems like I had the one that bolted to the top and bottom of the frame. I cut and removed the top braces because they are not needed and I just slide it so it was square in the frame and aligned with my trans mount then drilled some holes....done!

I went from a 250 6 cyl and a granny trans to a BBC and an M-22 4 speed. Just mocked up the crossmember where I wanted it, drilled and was done.

[63chevyll]

or chech the trans cross member.


even loosen the frame mounts untill everything is lined up, then tighten the frame mounts