Replacing PRAM battery

[Debbi Young]

Apparently PRAM batteries are due to give up the ghost about now on iMacs
built in the late '90s/early '00s. I have the replacement battery but need
to know if this is something you experts recommend having an expert do, or
can I replace it myself? I've successfully added memory to the machine, so
am not afraid to open it up. If you *do* think it's okay for a home user to
replace it, could you include instructions, or a link to some? I'm unable to
find anything using a Google search.

Debbi