i have a more than 10 year old imac g4 that i'm going to crack open soon to max out the memory. while i'm in there i'll replace the original pram battery. i'll also blow out the inside with some compressed air. anything else i should do while i'm in there? i will NOT be replacing the hard drive and optical drive even though they're old they seem to be working fine. i know about the thermal paste. i've never been inside one of these things before. thanks.