1997 suburban Conversion?

[pavegunner]

I'm really thinking about it. I have two vehicles 1. A 1997 GMC suburban 1/2 ton 4X4 with 170,000 miles in great shape no rust loaded with leather interior. 2. 1995 dodge ext cab long bed 3/4 ton 5. 9L Cummins 5 speed 2wd 230,000. The problem is that I need a 4x4 that gets good fuel mileage and is comfortable. With my truck I can get about 22MPG. Should I do this conversion or sell what I have and get something else? Also the engine runs great and does not leak, should I just put it straight in or check items before the install? Thanks Sean from Indianaoplis