1998 K1500 miss

[arcbb66]

I have a horrible miss now.  Started a year ago.  Was missing, so new distributor, wires, and plugs.  No change, so put a new spider injector on it.  Ran great for a week.  Then started missing again, especially under load.  Found out fuel tank had hole and pump was clogged.  New tank,pump, and fuel lines.  Still missing.  Took spider out and cleaned injectors.  A little better, then all of a sudden running horrible.  So replace the spider, started out ok but didn't make the first lap around the block.  Thought it may be spark since it's worse under load.  Changed coil, made it worse, even at idle.  Any ideas where to go next, besides back to a pre-72 and forget the early days of computers?  Never had this generation of engine.  Thanks!

[bronyaur]

Have you properly set the cam r e t a r d offset to within +/ - 2?  

[alpinecrick]

New fuel filter?  CEL on?