Well, I'd say either look for a normal LCIII motherboard or seek someone out with a broken LCIII board with a working CPU and get the chips swapped. It really shouldn't matter since an normal 16MHz '030 in a LCIII should outperform one in an LCII since the LCII has that 32-bit? processor on a 16-bit motherboard (address/data bus?) where as the LCIII should have a 32-bit motherboard (address/data bus?).