Are we talking a car or truck, because a '51 car bellhousing will not work with the later tranny because the bolt pattern is different. However, it may be possible to modify it, I'm just not sure what the differences are off the top of my head right now.
You can change the linkage or go to a hydraulic throwout bearing setup and ditch the entire mechanical linkage stuff.
A truck bellhousing will have corner mounts on it, so mounting at the tranny wouldn't be necessary.
Most S10 T5's are 4.03 1st gear. Not many with the lower 1st gears. Good luck...
