Extend - A - Cab, Need Help Please

[68gmcdually]

I am approximately 3 days away from taking the plasma cutter to my mint 68 cab to extend the cab 18". I wanted to keep it stock but I am getting married next June and I am hoping that there will be the pitter patter of little feet not long after. The truck chassis is not stock however, it is being remounted on a 1992 Chevrolet 3500 to allow for some trouble free drives, hopefully. If anyone here has done this type of conversion please let me know the overall outcome, and if you where happy with the results or not. Also if I go ahead as planned I need some ideas for windows, I tried to steal some corner windows out of my dad's '53 five window cab but I was threatened. Thanks alot for all of the great ideas on the dually idea.