just in case anyone is following (and more just because I fell like sharing), here is an update on the conversion.
- I bought a replacement/used fuel pump for the 12 tank on eBay for $60 (it was from a 14 with 102K miles)
- I put the tank in and discovered that the 07 and 12 use different diameter fuel lines... (also the EVAP connector is different)
- I pulled the the EVAP and fuel line from tank to engine from the 12 and replaced the ones on the 07
- The 12 has no in-line servicable filter (it's in the pump, except on the GT500), so there is that...
- I cleaned up the 8.8 from the 12 and painted with POR15 and replaced the pinion seal (reset the pinion crush to 8lbs/inch)
- The 8.8 is a LSD but has 2.73:1 gears, that may change later...
- I put the wiring all in the car and reinstalled the carpet, I started putting in the HVAC from the 12 and discovered the firewall needs to be modified... so it has to come back out.