Dangers of downgrading after installing GPS radio (and a little on signing)

[OJM]

[quote=ImCoKeMaN;276445]Ok there is a TON of confusion here, let my try to clear things up.

SPLs:
0.40 will be overwritten by a flash if an nbh includes an SPL
2.31 will not be overwritten by an nbh (only via OS aka unlocker 0.40)

Radios:
1.xx radios/non-GPS work with 0.40 SPL only
3.xx radios/GPS work with 2.31 only

Okay, here goes. I have bricked my phone and I think I can now figure out why. I believe that I may have mistakenly loaded SPL 2.31 BEFORE upgrading my radio to 3.xx. I then flashed the new 3.05 ROM (w/ GPS). My device is now inoperable. It gets stuck at the HTC splash screen when I reboot OR, if I enter bootloader mode (take out battery, put battery back in, hold camera + power) I get the red/green/blue/white stripes and it reads "VOGU100 MFG, SPL-2.31.CoKe, CPLD-3".

I have tried the unbricking process and but every Sprint original signed ROM I download won't work (i.e., I get an RUU Error message telling me that the file is corrupted - this happens with every link I have tried). Any thoughts on how to unbrick? I appreciate all suggestions.