Until the last 060 upgrade, my A3000 was overclocked from 16Mhz to 25Mhz, indeed it needs a new xtal (I used a socket to easy handling) and a heatsink over the 68030 just to be safe.
The jumpers were:
J100: 1-2 (old 2-3)
J151: 1-2 (old 2-3)
J152: 1-2 (old 2-3)
J851: 2-3 (old 1-2)
