The last time I looked, GRiD machines had a large following on the net. Many websites, user groups, etc. Perhaps google will be your friend here too. You might also want to check Yahoo Groups, et.al. If you manage hook up with other GRiD fanatics, they may be able to help you get a bootROM burnt for it. (I'll be happy to do the burning, if you find the necessary info, and if it's within the capabilities of my system).
--T