trans issues
I had a similar issue with a c-4. I never did find the problem. Ended up going with a different transmission altogether. A powerglide. I had the c-4 built 3 times,changing bands,servo, valve body and still when I simply put it into gear, nothing.
That trans is sitting on the floor of my shop fresh but questionable.
I know this doesn't help but responding as I have been there,done that.