I remember having had the same problem in a towered 4000D with a second party ZORRO busboard, i think it was an eagle busboard. I thought it might have been the caps.
Now I have the 68060 upgraded different warpengine, from staccu poland.
That one doesnt like the picasso 4, endless resetting.
When no scsi harddisk connected it doesnt boot.
Otherwise its rockstable and super fast with a uwscsi hd.
What Rom do you use? What 68060 libraries.do you use?