How goods your tool selection.
If you're not well set up on tools,your best bet is probably a muffler shop.
We put a 22" Magnaflow on Audio's truck,and it took the better part of an evening.
In fact i swapped my whole exhaust for a Magnaflow dual set-up in about the same amount of time,as doing just his muffler swap,
Although we did it the hard way,lol.
Andrew can probably set you up with an aftermarket Magnaflow kit though that is a direct bolt-on with all the piping and adapters already installed