so i went to get an alignment today. they found a cracked upper control arm on the driver side, right at the upper ball joint. im on the hunt for for a replacement. parts manager at my local dealer said he could get me one. there is one part number for 90-92, 3300 or 4000lb front axle. 93 had two different numbers, one for each weight rating. my truck is a 92. 5. how do i know which one i need? anybody with a line on a good, but used replacement, please contact me. im out of a truck until i get this fixed.