I have been an IMA for almost 5 years and would like to get back into flying in a ANG/ AFRES unit. I was a C-130 navigator and then transitioned to an Army Aviator as a warrant officer to fly helicopters. I discovered that the Army life, QOL, and 1 year deployments weren't for me. Got 're-commissioned' into an AFRES IMA staff job and got the itch to fly again. BTW, I go for my O-5 board soon. Any suggestions?

I haven't made the jump from IMA to TR reserve yet, but my understanding is that it's the same process as if you were anyone else - start pulling contacts you have at units you are interested in, or identify a unit you want to join and start knocking on doors.  After getting hired, the paperwork folks at the new unit should generate a gaining order and transition you over to the TR world and get you on their Unit Manning Document. 

I'm sure it's much more difficult than I've written it, but I think that's the big picture process.

If you're asking which unit, then I suggest you just go to the AFRES website and see which units interest you.