Uh... lets back track.
I'm assuming 4x4? What part of the exhaust is in your way? IIRC, the stock exhaust shouldn't bump into anything. If it does, just stack it or dump it before the rear wheel? No reason to keep the stock exhaust anyway, it's junk (in my opinion).
My tailgate on my truck probably sits at around 5'5 or so. I don't think my girlfriend is taller then it. I'll check on that later. The rear springs and such are easy to put in. They'll need a bit of time to "settle" so to speak, so bare that in mind. You may have ended up with an extra inch or two, but after riding around for a day you'll come to find that it lowered itself.
Do you have an RSK on the front or rear? Those will play into your height factor too. Things to think about.