Harmonic balancer indexing...

[DennyB]

I'm replacing the stock 72 307 with a 74 350 in my 72 C20.
The 74 350 had a long water pump with the timing tab mounted to the timing cover near the middle behind the water pump. The 72 307 had a short pump so that is what I'm using to keep the ac, ps, etc pulley alignment correct.
Here is the problem...
I need to use the timing tab that mounts on the side of the timing cover.
I've tried original 350 the balancer.. no good. I tried the 307 balancer (which is much smaller) no good. I even pulled a balancer off a old crate motor here with the side tab....even worse.
The 74 had #1 on the distributer one behind the 307. I can change the clocking of the distributer to work but the balancer should be on 0 when at TDC
What am I missing?? Am I having a total brain fart? What balancer do I need?
Did these motors have different cranks/cams? I though they were all the same.

Thanks all.

Denny