need help with my truck

i got a 88 gmc 1500 pickup and it has like a digital heater control on it. last week after about 5 minutes of driving it blew the fuse on it, so i put a new one in and it blew instantly. so i was thinking it was a short some where, so i started taking off some of the dash and moving the main heater control wires around trying to just see if i can move it off the spot where it is shorting. well after i moved all of the wires around i stuck a new fuse in there and the heater controls worked, but after about 30 seconds there was a ton of smoke coming from the dash and a bad burning smell, but the fuse would not burn out. i am really just looking for a quick fix here guys it is only my $500 winter beater, so any and all advice would be helpful.
thanks,
steve

well i found two wires that were completley melted and burnt, now my question is how do i know what started this? i mean if i just splice 2 new wires in there how do i know that the same thing won't happen. i really know nothing about wiring so any info is appreciated

hey thanks for the help guys. i ended up just cutting the two burnt wires out and my blower motor works with out them, so i am just going to drive the truck like that. it is only my $500 winter truck so i am not too concerned if other stuff isn't working properly.