That sucks, at least your on the good path now. My RamJet would do great until a few miles of crawl in low/low at high summer temps. Then it would studder to the point of shut down. Stopped, looked around, didnt see anything, obvious anyway....waited about 15 minutes, started up and BAM no issues.......Till we got up in elevation, ambient temps were in the 90's and then it would start in again. Cracked the fuel line at rail to check for fuel pressure and had fuel. Pack up tools started up and BAM, no issues again, drove it home no problem....Thought maybe bad fuel, water or whatever. All the while I had thought it was a wiring issue as I had plenty of fuel at the rail or something in the intake with that motor.....Then fast forward this happening a few more times, until I pull that motor and drop in a BRAND NEW LS3.....took it to Moab, did Moab Rim, got up to the sand, temps were in the high 90's and the same dang thing was happening. Now I figured out this has NOTHING to do with my Motor or wiring, but placement of the fuel pump, which is mounted on the frame. NEVER ever had an issue on the highway, ever....only when locked in low and temps were high......Spoke with a buddy of mine who restores Cruisers, and before I finished my story, he told me I know your issue. "Take out that stinkin frame mounted pump and fit it inside the tank"...He said the first 20 or so restos he did, had the same issues. Went with Aeromotive in tank pumps and has never ever had an issue since. I dropped it off at his shop to do it for me, thats why I stated I will report back when I pick it up. I sure hope this is the same in your case....All the hours of thinking WHAT THE FRIG IS DOIN THIS takes its toll.....but.....this is our passion so we stick it out......Now im just getting started on another build on my 96 cherry LX450 and will keep the oem 6cly until i can take it as it sure is a slug !!.