OP, do that. Here you find all needed info:
http://www.lbodnar.dsl.pipex.com/eMac/eMac-upgrade.html
BTW, Leo Bodnar is MR member, so you could ask him if you have additional questions
🙂
I'd like to get 1.42 one and check it's OC abilities. 7447 CPU has potential and this eMac multiplier PLLs are scaled to 2.0 GHz
😀