The fuel pump ground is a direct line to the engine block that picks up several other grounds along the way. I found that out the old fashioned way. All switching is on the power side. I could have made a new ground on the body near the gas tank and solved this long term. By shear luck, this also would have bypassed the bad splice. But at the time nothing was making sense and the problem was inconsistent, so I kept looking for something in case this was the start of a even bigger problem.