C3 Auto to Manual Transmission Conversion

[Brad T.]

I am doing a frame up restoration on a '69 coupe. It was originally an automatic car but I would like to convert to a manual.

Can I use the automatic transmission support cross member that bolts in (GM P/N 3987886) or do I need to install the welded cross member that welds in place to the frame (GM P/N 39878840)?

[Joel A.]

Re: C3 Auto to Manual Transmission Conversion

You can absolutely use the auto crossmember...makes it much easier, anyway, than the welded in one of the 4 speeds. You'll need the mount bracket, and you may need to add a few holes, or do some welding, but the crossmember itself will work. Most folks go the other route...from 4 speed to auto w/overdrive, and still use the welded in crossmember.