test pipe/cat delete install....wth

so I finally got a cat delete to go with my cai…..I was told and read best bang for the buck leaving stock exhaust on......well besides better suspension,which I have...so does this thing just come out or do I have to remove the side panel....hoping to just drop it without removing ...well you know...has anyone done this without removing side panel....any tricks that have been learned....any advise/wisdom....any thing would help.....looks a little tight...can I leave muffler in place...to me it looks like the springs could be a pita....help please....