spearman

Hey there, new to the forum but looking for some advice. Dealer says that my catalytic conveter needs to be replaced ('03 OBW w/ 105,000 miles) the increased RPM's and lack of power along with decreased fuel efficiency seem to confirm this. What I'm wandering is, is this something I can fix myself? I've done some work on cars in the past, but not on this particular one. I met a guy today who told me that this really was a piece of cake since it's just a bolt on. He suggested buying a grinder to get the bolts off and then just putting it in myself. Any suggestions or ideas on this? Thanks