Have a 1975 all wheel drive pick up with a 203 case are they junk? anything special to converting it?

About 25 yrs ago they had a kit to do that, it had the lock out hubs included. l did not see a significant improvement in mpg. So i'd say do not bother.

You would probably be very disappointed in a conversion,it is simply not worth it.

yes & yes. l personally hate the 203, especially in its stock form. they do sell part time kits if u want to polish that turd, just google around. l had one in my first k5, it came like that so l didnt install it, it worked for like 3-4 years untill it started poping out gear which happens to alot of other people. in my opinion if ur going to take out that 200lb boat anchor of a transfer case put a different transfer case in its place. though u cant just bolt one up, u have to get a different output shaft & adapter.

im running the aluminum 208 in my 85 k5 in place of that 203 & couldnt be any happier.