I tried to flash my 2500 with the Mad dog 2F8 and it is working and recognised by windows as 2510.
But when I try to flash it with 2F9 this message appears:
Target NEC ND-2510 is not found Correectly.
You need the bin file from this site:
Then use BinFlash from the utilities page on that website to flash the appropriate bin file on the drive. Should work fine. Good luck.