Diagnostic help please
 

This one's driving me nuts, I have a bone stock 78 Z-car. When the car hasn't been driven, and the car is cold, it always starts right up, If I drive it and get it to normal running tempature, then shut it off, I will not restart. After it sits for about an hour and a half it will start right up. Its getting fuel, but no spark. I've checked for spark at the coil and it has none. I've changed the coil but did not help. For the heck of it, I tryed a new Transister ignition unit but still have the problem. I do have another running 78 z that I can swap parts from but I just don't know what to try next.
Any help would be greatly appreciated.

problem found, kinda, I swapped distributors in the two z's and the problem jumped to the other z. I think it may be the pick-up coil in the distrbutor. I checked the air gap, It was .50, I adjusted it back to .30 but the problem was still there.
Anyone know where to buy replacement parts for the OE distributor, I guess I'll be buying a pick-up coil.
thanks.

www.thezstore.com

www.blackdragonauto.com

www.courtesyparts.com