I have an Amiga 2000 rev. 4 with kickstart 1.2 and was planning on upgrading it with a SCSI HDD controller, kickstart 2.04 and an acelleratorboard (type 2630 or something like that) but after reading a little more, it looks like the rev. 4 board is no good..
Would you be able to check something for me on your A2000? When you run the SetClock command from a Workbench 1.2/1.3 disk, does it print a message like this:
Warning: Clock is at old address
or
Warning: clockchip found at $d80000
arrange update of mainboard as soon as possible