Here is my 83 mm with 4d55. Started as 2wd diesel with A/C and no power steering. Rebuilt engine, turbo, and added P/S. Then put 3 inch lift on it. drove as daily driver for one year until 18 yr old in yukon took out my front clip and frame. I looked on craigslist and found 85 Ram 50 4x4 with bad head for 600. insurance gave me 3500. So i hopped plane, rented uhaul and brought it home to socal. i used frame from 85 with all components except trans. and fuel tank. I had a 83 diesel 4x4 trans. already and had it rebuilt. Front clip and grill is from 84 MM. I removed at firewall and installed on my cab by opening where sheet metal is laminated around front clip section like factory. Had to use spot weld cutter for all welds. Also had to open radiator support at bottom to pass A/C lines through without losing freon. Everything then attached solid with wirefeed weld. Also floor panel from 4x4 for shifting. 3 inch lift is not enough clearance. Also to look factory. Basically 18 yr old paid for everything not including labor. So next is the ultimate mod to complete project, extended cab from my 84 just bought for purpose. Frame will need to be lengthened 30 inches. I will take more pictures. for my repair/conversion to 4x4 i only had for measurments etc. So here is the Before pictures for now.