New motor tunning

Heres what I have so far. I put a sbc 355 with 190 heads and a mild cam into my 93 gmc jimmy 2wd. I have roller rockers and a 600cfm edlebrok carb. This is on a 700r transmission.
Heres my problem. I am guessing at this point. I think I set my timing good for a good run but when I turn the car off and try to turn it back on the starter struggles and then misses all together. If I pull back the timing it makes it easier on the starter but still struggles and then my truck runs horrible and upfires when trying to go into passing gear. Whats up with this. I am starting to get angry with my truck. Any suggestions?

P.S. I am not sure I tuned it right from the beginning so maybe steps for initial tune would be good . i.e. setup on #1 and so on.

Are you sure the carb isn't running too lean? Did you advance your cam any past 0 degrees? What sort of ignition are you running? Are your rockers tightened down too much? Are the plug wires in the right spot on the cap?

Take a look at the advance mechanism for the distributor. The system may not be 'retarding itself when it returns to idles or is switched off. The weights may be rusty or have weak springs, and/or the vacuum can is sticking.