charging issues

still running great after 7 months, charging the way it should and everything working normal.

i recently had a problem develop. i would turn the key and it would not fire until the key was on its way back to the start position. i would crank it a few times , then it would start. it gradually got worse until it would not start at all. i pulled the ECU box off, stuck a new one on there, it fired and ran immediately. then a couple days later, it happened again. im thinking WTH? i pulled the ECU off, took a flap disc to the box mounting tabs and the fender apron where the ECU mounts and sanded all the surfaces to bare metal. i re-mounted the box, it has been working flawlessly for 2 weeks now.