The center sector of the FoMoCo T5 shifter will fit in the GM T5 shifter housing. I am running this combo in my 54 truck. However, the FoMoCo housing is too large. You'll have to pop out your old S10 center and stick in the new one.
The advantage of running this combo is that the FoMoCo has provisions for BOLTING on the stick of your choice and have it rubber shock-mounted.
The GM S10 shifter depends on the rubber insulator inside the S10 shifter rod. If you don't run a rubber isolator you may be bothered by some annoying vibrations that transmit up the stick. Secondly, you can pop off the stick to get your bend angles perfect without having to remove the housing itself.
I cut off the front lock ear from the GM unit...swapped in the entire center assembly and tacked the front. I have some pics in my album.
Hope this helps.
Dave
