At a total loss for an explanation

Gotta do basic troubleshooting man, throwing parts is time and money. Like my touch the coil wire to a tongue suggestion, thats checking for spark. Seriously, get a Chilton Manual, I think they still sell the big hardback manual that has a troubleshooting section and follow a logical process. You may need a fuel pressure guage and a multimeter to check grounds etc, but throwing parts at it is like findi ng a needle in a haystack. I agree with running it till it dies, then checking for spark and fuel. That will get you on the right path.