&Tahoe
I have a WarpEngine in my A3000 and the onboard SCSI works just fine without the INT2 mod. The WE uses a jumper rather than the int2 mod.
@mousehouse
As far as accelerators go, I would love to have a Cyberstorm 060 (any MK) for my A3000D, but they are very hard to come by. If you can't find one, the WarpEngine is a good alternative for an 040 based card.