I have an MKII in a 3000D as well. No INT2 change and am using the onboard SCSI to boot and the external port for a couple of other devices. The on board SCSI is fast enough for me and I haven't felt the pressure to up-grade.
The active terminator is a good try if you have problems. My system didn't need it but it helped me on another 3000 with a Warp Engine.
JLW
