My understanding was the hummer stuff fit to the metric housing we have. So would the lc3, but I'm worried about making the 4l60e fit in the same place as the 30e, I'm wondering if anyone knows the physical size differences? Or differences in mounting location? Any pictures etc. I've gotten over wiring as the Holley dominator efi will handle the 4l60e and tuning just can't figure out how to tune a factory transmission for a new motor...