Maybe a standalone 16197427 94-95 TBI computer would be an option? The link below has information for the 4L80E, the 4L60E would be similar:
https://sites.google.com/site/astros...h-16197427-ecm

Maybe the 1975 C10 has a HEI distributor that can trigger the 16197427 computer.
Maybe there is a way to fabricate a Throttle Position sensor to the 1975 C10.

dave w