Wanted to post this as there is very little on this anywhere on the internet.

The Lower Control Arm for a 1998-1999 ZR2 is unique. GM is the only provider of this LCA, their are no after market equivelants. I went so far as to talk to MOOG directly on this.

For reference, the OEM part numbers are:

15777765 driver side lca ZR2
15777766 passenger side side lca ZR2

The following part numbers may be OEM substitutes:
12472993, 12472994

One dealer in the USA had the 15777765, they are in TX, I purchased this earlier today.

Ebay does have these part numbers show up on occasion by OEM part liquidators.

I am going to keep the original LCAs from the ZR2 , rebuild them, and keep them as spares.

Being that you just purchased these from a dealership, were you able to probe and see how the supply chain is looking on these? Does it look like they are starting to dry up and most interested should move on them now while they can, or simply cruise ebay and ****** them when they show?

EDIT: Also, what is the difference between the 98-99, and the 2000+?

These LCA are discontinued. GM is making no more of them. According to GMs nationwide dealer network parts inventory, there are two 15777766 available and zero 15777765.

Some places specialize in buying parts of dealers that go out of business, they may have some of these.

I don't know what changed in 2000 with these LCAs, something I will be checking out.

I believe the 2000+ ZR2s use Lower Control Arm GM part # 15777767 for driver side. I bought one of these by mistake for my 98 ZR2. I did a visual check and see no difference between the 15777765 (98-99 ZR2) and the 15777767 (2000+ ZR2) Lower Control Arms. I have yet to remove the LCA, the visual check is with the LCA still in the frame of the 99 ZR2.