1977 Chevrolet Blazer

Engine Performance problem
1977 Chevy Blazer V8 Four Wheel Drive Automatic 90000 miles

I put a 1984 4bbl intake manifold onto a 1990 chevy 350 which was fuel injected, I switched it to carbureted. I installed a new hei distributor, holley 600 cfm carb, new spark plugs. I cannot get the engine to idle on its own it runs real rough and you can smell the exhaust real rich. What is the correct installation for the distributor, what is the correct timing isit 8 degrees like it is on older 350s?
or isit 0 degrees like it calls for on the injected 350. I can get the 350 to start but I cant get the timing right. I set the harmonic to 8 degrees btdc on #1 hole
distributor points to #1terminal but it runs like crap. PLEASE HELP ME I AM AT MY WITS END WHAT DID I DO WRONG?
June 25, 2009.

Have you adjusted the carb fuel air mixture? Any vacuum leaks? I believe 8 BTDC should work. Does the engine run well when on the road off an idle?