I've ordered the downpipe (plus the cat) to avoid any need for welding. However I went out yesterday to try to get the old pipe/gaskets off and the bolts will not move. After soaking the bolts with some liquid wrench and PB Blaster one of them finally came off (the front end). The others will move at all, even after the penetrating oil.
Would anyone know what else can be done to help take the old bolts out? I’d rather not start cutting things away and running the risk of the new pipe not fitting.