how do you know that the 060 on your card is dead?
it can be another thing....it can be the connector
on the other way...you can install a 040 there but you must know what are you doing...there are 3 types of 040 cpu...25mhz,33 and 40....and each one of them needs a diferent crystal oscilator and of course you must remove the 3.3 regulator cause the 040 works at 5 v
and about your question :all you want to do is posible....blizzard and apollo 1240/1260 boards can be upgraded or degraded to a diferent cpu but it's not simple
on the other way if you haven't a tower you can't put a 040 on the normal A1200 trapdoor...it needs a fan and the 040 not works fine there jailed...it suffer very much by excesive hot
bye