I did it! (I must be a Caveman!) 
I used pwnage 2.0.2 and my MacBook to upgrade from 1.1.4 my 4 Gig and my 8 Gig backup (I got when AT&T was selling them as refurbs).
Nice, I just used the custom firmware it created (I didn't have to "unlock" twice!).
Everything works on T-Mobile (note: with Total Internet EDGE).
Rather than try to look into the different threads, feel free to ask questions here... I'll do my best...
EDIT: BTW, I used this guide:
http://www.modmyifone.com/wiki/index.php/Pwnage_2.0_Guide
I used pwnage 2.0.2 and my MacBook to upgrade from 1.1.4 my 4 Gig and my 8 Gig backup (I got when AT&T was selling them as refurbs).
Nice, I just used the custom firmware it created (I didn't have to "unlock" twice!).
Everything works on T-Mobile (note: with Total Internet EDGE).
Rather than try to look into the different threads, feel free to ask questions here... I'll do my best...
EDIT: BTW, I used this guide:
http://www.modmyifone.com/wiki/index.php/Pwnage_2.0_Guide