[yimmy0917]

I built a 350 to through in my wifes K5 blazer. It's a completely stock block that came out of a 96 Youkon. I through the rest of it togather with parts I had around the garage.Mid. 70's heads, Performer intake, Eld.600 carb. I just don't know the best way to get the timing dead on (or close to).

 

[Cheyenne'88]

Vacuum gauge is a good way. Check out scenerio 11, here:
http://www.secondchancegarage.com/public/186.cfm
Also, you basically want to time to the highest vacuum, then back it off an inch (of vacuum) or 2.
This is also a very good tool to adjust/set your carb. Do a search, there's lots of vacuum gauge stuff on the 'net.