Anybody know the difference in steering boxes over the years. I was on the PSC websight and it lists a different box for 77 through 79 than 80 throgh 87. When I got my 2wdr box for my crossover I didn't even see what year it came off. It worked so I guess I got lucky. The reason I ask is there is a psc steering box for sale locally that is ready for assist. Would be perfect if it would fit my truck but I have an 87 and this one is for an77 throgh 79. Is there a way to make it work?