I just replaced the 2" with a 4" on my 86 K5. I took it off an 84 and I took the whole differential. When I took the driveshaft off of the 84 it seemed like it was barely in the tail shaft. Question is; is anyone running a 4" with stock driveshaft and if so have you had any problems while off roading? One more question, I just swapped the rear out tonight and haven't even looked at the front. Am I looking at a lot of work or is this going to be as easy as the rear?