Carb idling problems on 65' C-10 with 292

[runningiron]

Need some help with my 1965 C-10. It has an original 292 with approx 158K miles, 3 speed on the tree. Recent tuneup, new plug wires, plugs, dist cap, points. condenser, new fuel pump and rebuilt 1 barrel Rochester with manual choke. Stock exhaust. I timed it 4 degrees btc, dwell at 31. It is hard to start and takes what seem to be a long time to warm up. The carb stumbles and pops back through the carb at times, not all the time. What am I missing here? Thanks for any info in advance.