Thanks for the measuring and pinion tips...
There is no way that I can use the wheels and tires I want without narrowing the housing. I am going for Pro street type of truck. The wheels/tires combo were selected on appearance and the deal I got.. The rear housing will need to accomodate. 18" wide Sportsman S/R radial and Centerline warrior wheels
As the other fellow said many folks buy the wheels they want and work backwards to figure out the appropriate width for the rear. Same here, only want to do the drive train on a spare frame and transfer the body onto it once the drivetrain is complete. The fellow I am purchasing many parts from has a housing but I will not be able to use it unless I narrowed it further and bought new axles.
So I am not purchasing it... Once parts arrive I can determine the width I need.
In the mean time, I figure I would try to get some advice