Cat back help kinda

Hello everyone, so I have a 05 legacy that needs a new exhust so I found one but its a 3 in( more like 2-3/4) and I'm trying to hook it up to the stock cat but I can't find an exhaust adapter for that, all I keep finding is a greemspeed DP to OEM cat but it says on the website that it is not to be used others wise. My question is has anyone used this setup on oem cat to mid pipe, or do u guys suggest cutting the flanges and getting a sleev adapter to clap together. Will it push the exhust to far back where it won't line up? , oh also on the muffler the rod that is welded onto the car were u hang the muffler on is rusted kinda bad anyone replace that and if so is there a link to where it shows how to do it. Thanks in advanced

This is what I keep finding

http://www.grimmspeed.com/catalog/pr...roducts_id=224

That adapter is for 3" DP-2.5"Mid I believe. It won't work for you. You can do what you like for the exhaust but I think you'll need the joints for expansion. I could be wrong though. Just speculating.

You should be able to get away with the stock donut gasket shoved into the aftermarket mid-pipe. I've done so myself previously with no leaks.