I took mine out. They weren't rivets they were pins and the baffle was press fit on them. I think I remember prying off the baffle with a plethora of screwdrivers and pliers lol. In the process I bent it up pretty good, but it all hammered back down when I reinstalled it.

Mine had a lot of carbon buildup. If I had to do it over again I don't think I would bother taking it off. Theres nothing underneath it except empty cavities . My rebuild kit came with the proper gasket to replace it with.

Also, I tried everything to get the carbon to come off, 3000psi washer, soaked in mineral spirits for a week, wire brush, ect.... Only thing that remotely worked for me was soaking it in simple green and using a very small wire bush attachment on a drill.