This is my first tutorial, so bare with me. And I apologize if this is in the wrong forum, it seemed most appropriate. I performed all this in Windows 7 x64.
First you need some software-
1. QPST - http://www.mediafire.com/?m4s81a4zsdbmhen
2. HTC Diag phone drivers - http://www.mediafire.com/?631456zwxi09hh2
3. PRL File 60650 - http://www.corolada.com/prl/
4. I'm not sure if you need ADB installed, but I already did.
5. You will also need to know your MSL. It will most likely be 000000 if your phone is coming from Cricket or MetroPCS.
Now that we have those, we can get to work.
6. Connect your phone via USB and type in ##3424#, your phone should now be in Diag mode. Make sure USB Debugging is ENABLED!
7. Open your device manager in Windows and right click the unknown device "HTC DIAG", Select Update driver.
8. Select Browse my computer for driver. Click select device from list, Click next, Then click "Have Disk" and point to the appropriate HTC Diag driver folder you downloaded.
9. You now should have HTC Modem installed correctly. Right click on it and go to Properties, Then click on the modem tab. Find your port number eg. COM1, COM2, etc.
10. Open up QPST Configuration, Click the PORTS tab. On the bottom right click add port. Add the port you just found from the step above, and hit Enable.
11. Go back to the active phones tab, double click your phone.
12. On the bottom click read from phone. Then save it for a backup.
13. Click on Roaming tab. Find the PRL box, click browse and add your 60650 PRL file you downloaded.
14. Go back to the CDMA tab. Under phone number click the Class 1 box. Enter your phone number (xxx-xxx-xxxx) minus dashes in the box next to Class 1.
15. Click write to phone. Hard parts over!
16. Once that finishes, unplug and reboot your phone.
17. Go to Settings>Update Software>Update PRL then reboot again.
17. Once its back up go into your dialer. Punch in ##3282#. Hit Edit Mode. The password is your MSL.
18. Once in goto Data Profile. Hit Menu then hit RESET.
19. Your phone should now reboot and be able to activate on Sprints network!
I already did this for my roommate, so I am writing this out of memory. I wanted to post pictures but I would have to take CM7 off my phone and redo all of it... grrrr.
Again, this is my first guide so i might have missed something. But I hope not. So many people have helped me here on XDA, so this is my contribution to the community. I hope this helps some people.