Whoa, wait - Make sure you get them right. Most ROMs will fry if you reverse power and ground. My A2000, A4000 and A1200 had markings on the motherboard next to the ROM sockets to denot where pin one was.
It looks like a line with e a U divot out of it. To show where the notch in the ROM should be. -----U------ I appologize but I've never been lucky enough to own a A3000 let alone a tower version. I think they used to have a notch right out of the socket to denote pin one orientation.
A3000 ROM install from SoftHut