I have for sale a used DataSystem Rspec ASG633 Limited Air Suspension controller. I was going to use this for my other vehicle but ended up going a different route. This controller plugs directly to your OEM air suspension ECU and allows you to easily control your ride height without spending thousands on an aftermarket air suspension kit or coilovers. This unit is designed to work for the 89-94 LS400. However the harness I have is for the 89-92 (Before Sept.). If you have a LS build after Aug. '92 you will need a different harness. The controller retails for over $500 with harness plus shipping. I'm asking $300 shipped + paypal fees
. No parting unit with harness!
Here's a couple links about the product details
Link to Rspec website
Translated DataSystem website (more info)