If you want to stay 6-lug the best way is to buy a kit. When you factor in that you don't need to find and buy a 5-lug rearend or 5 lug wheels the price ani't that bad. Here's one.
http://www.gmcpaulstruckparts.com/Brakes&Steering.htm
------------------
72 GMC Sierra SWB almost finished---- 84 Softail
Olive Branch MS
__________________
72 GMC Sierra SWB almost finished---- 84 Softail
Olive Branch MS
|