3inch exhaust reduced?

[LS short box]

I like to run 3" from the headers to a 3" muffler inlet. Then 2.5" tail pipes if room is limited. If you have the room I'd go 3" all the way.
I would go with an aftermarket mandrel kit or build it out of mandrel bend pieces. Muffler shop tubing benders really squish 3" tubing when they bend it.