hi everyone my name is marc and I have a 86 c10 longbed. I pulled the v-6 out of it and replaced it with a v-8 5.7 with vortec heads. I placed a lot of add ons like a Holley carb 650cfm , headman headers, dual exhaust, KnN filter, and Optima battery. It ran like a champ for a while until one day as I was driving to work it just stopped. I could get it started every now and then. when I say it stopped I mean no power at all. these are the things that I have changed out: starter, ignition switch, battery, key cylinder, fuses, buzzer. I thought I had a short in my system because I could start it some days and sometimes nothing at all. When I try to start it I get nothing, no electricity to the dash , no buzzer, no sound to the fuel pump, nothing. I am getting power to the starter but the starter doesn't turn and I made sure my body ground was clean. My engine ground is good too. I AM STUMPED. I need help. I thought it was the ignition switch but I replaced it and still nothing. ANYBODY HELP ME SAVE MY TRUCK