Your main ground should be on the engine. I then have a ground strap to the body from the engine. I'm sure it would work grounded to the frame but from my research running the cable to the engine is superior.
I did the same thing. I have a ground from the battery to the block and another to the body. I know grounding to the body would have been good enough, but I chose to run both based on personal experience.
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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