Setting timing for /6 with new electronic distributor

Ive been messing with slants for a long time.Start at 8* before and like Rusty stated. Work your way up from there.Maybe 12* might be max to run on regular 87.It may take more.We in Nevada have some poor quality pump gas.I have found that at 2500+ altitude they also don't like more than 23-29 Degrees total timing.
These are my findings, yours may differ. 63 Valiant's are cool.