module or ballast resistor?

hey guys- what do ya think this is- 83 pickup sno-commander, 318 2bbl, newer 100amp alt, bypassed all vital gauges in dash(temp, oil, amp) put in mechanical gauge pod(temp, oil, volt) and everthing works fine(installed last summer). About 3 yrs ago i swapped the cab, removed the rusted out 83 cab and put a 90 cab on. used all 83 wiring in dash under hood everthing is basically 83 exept for 90 cab shell(only cost 150). also replaced all relays under hood(start run, voltage reg, module all new exept ballast resistor)
ok to the problem- last winter when plowing, when truck got hot, would stall and i had wait 5-10-15 minutes she would fire right up and run great, happened 2-3x. ok I had another module so i swapped it cause i figured htat was it. didnt really snow again, dont relly use the truck everyday, but every time i used it since she ran fine.
this brings me to couple of days ago i knew it was going to snow so i fired her up ran a couple of errand she ran great, wednesday- snowed like a bitch, went to start her up, nothing just cranked, not getting really good spark at plugs, so put in new coil and plugs, fired right up. pplowed my driveway drove about 15 minutes away pulled into another driveway to plow- stalled- 10 min later fired right up, plowed for about 1/2 hr(long driveway/street) started to go home- 15 min away- everytime took my foot off the gas felt like she was going to stall- some popping, weasing, backfiring- got to a red light -stalled- 25 minutes later fired right up drove home, parked it haven't touched it since.
ok- Module? Ballast Resistor(limits spark)? Bad Ground? any ideas you guys have would be great, considering dumping some gas on it and have a barbecue mid winter!!!!!!!!!!
thanks- pete