Will this hd2 rom work on the hd7 since they have almost the same hardware?
I would NOT RECOMMEND using a ROM that was not built to go with your specific device. If you use a ROM that doesn't go with your device, even if the ROM goes with your device on a different carrier, you risk bricking the device. Make sure that your device specs match EXACTLY to the ROM specs.
Rule of thumb when it comes to ROMs:
close only counts in horseshoes and hand grenades.