Sprint TP2 on Tmo Edge/3G Radio Support

[quantumtransfer]

Currently I'm using Sprint's version of TP2. I have used the rhodium unlocker and I am currently able to use T-Mobile as my primary cell carrier. I have searched around alot online and through XDA/PPCG and found alot of folks that can't access 3G speeds on T-Mobile/ATT with their phones. I did alot of searching and i found that TP2 only supports HSPA/WCDMA: 850/900/1800/1900 MHz. With this said a Tmo TP2 can get 3G but a CDMA based TP2 can't.

My main question is..

I have done part repair on a G1 before and the radio was detachable, is there a possibility that you could frankinstein a radio from a Tmo phone and put it in a sprint phone? If its a hardware limitation that should fix it.

Another question..

IF this is not possible and or is not a hardware limitation is there any way to modify/reverse engineer a radio file for a GSM TP2 to find out the programming to make it work on the 1700 MHz spectrum?

Im pretty new to the scene and was wondering these things and didnt see any mention of the above in either of the forums.

"no body knew SPL's could be changed in the beginning until someone tried and succeeded"

Let me know your thoughts...