For Sale: Gear Vendors OverDrive unit. ( http://www.gearvendors.com/index.html) Set up for an NP205. All parts intact. According to the manual, this unit can also be used on other transfer cases including an NP203, NP205, NP208, NP241, and a BW1356/1370. There is a coupling that goes between the GV unit and the back of the transfer case. If you don't have an NP205, I would suspect you can buy the appropriate adapter for your TC. I had planned on keeping it but after installing a 6 inch lift in the Blazer, the driveline angle is too steep. This unit is ideal for a no lift Blaze,r or Suburban or a pickup with mild or no lift. It is essentially a gear splitter and give you six speeds, including an overdrive. Current price from Gear Vendors for this unit (3D0205) is $2700. Selling for <font color="red"> $1000 </font> Send me an e-mail to email@example.com or PM me.