I've got a 1973 K5 with an NP203 transfer case. It's a daily driver and of course the gas mileage is horrific . As much as I like the fulltime 4wd I'd like to make the conversion. I'v seen references in the forum to two Mile Marker kits. One's refered to as the "cheap conversion" and the other the "good conversion". What's the difference? Any other suggestions regarding this project? Different kits? Different companies? Different transfer case? I'd like to keep it as stock as possible. Thanks again.