Well, aside from wires being switched around, forgetting to plug in the connector on the distributor will also cause some issues.

 

This edit of the image that Captain posted above that I did a WHILE ago shows the trace layout on the cap:


If you have never seen a cap like this, then you haven't been working on any mid-95 through the middle 2000's Chevy trucks (whenever the coil per plug change took place). The V6 & V8 distributor caps are all pretty much like this. It simplifies the plug wire routing.

 

The cap is designed like that to reduce crossfire in the cap. If you follow the terminals, it follows the firing order 165432. Make sure you put a dab of silicone dielectric grease on each terminal, inside and out, of the cap. Don't waste your time and or money on aftermarket caps, stick with AC Delco.

 

If AC Delco caps are still made as they were years ago with the aluminum terminals then there are much better caps out there. Wells Gold, Accel & Summit Racing caps all have brass terminals are are higher quality then the AC Delco.

 

Yes, AC Delco caps use aluminum terminals.

I can't tell you how many aftermarket caps I've replaced with AC Delco ones on 4.3's with a crossfire problem. Could easily fill a trash barrel with them. Use silicone dielectric grease and make sure cam retard is within specs and they'll go 100K miles. Never seen any aftermarket cap go that long without a crossfire problem, it just doesn't happen.