I have seen a dead 030 throw yellow screens (just like if the daughter card was removed), don't know if that helps. Acill is right, test with a cpu board to make sure.
I have seen lots of 3000s in my life, from my experience the PALS going bad and bad traces/vias are 99% of the failures I have seen. Caps never go bad on the 3k. I doubt it is the CPU.
The real nice thing about the 3000, if it is well maintained and never had a battery leak, and the PALS were replaced with GALS, the darn things never fail. Make sure that you diligently clean the board, the acid leaks everywhere, so neutralize the entire board otherwise you may have future problems.
