[The cap'n]

First, what caused the ground wires to fail? THAT would be my first thing to look at. The loss of spark when warm/hot is a common Permatune failure, despite what their help line says. I've seen this failure with new-out-of-the-box units. Personally, I'd find a Bosch core unit and have it reconditioned by one of the folks here who do that (Loren or Ingo). Then you can use a Bosch Blue coil.

The Cap'n