I found a local add on craigslist with variuos tags and vins for sale. One pic is of a z-11 tag. What the?

From the CRG Website....

"Pace Car Replicas Replicas of the pace cars were also white RS/SS convertibles with white tops ordered under RPO Z11."

Also from CRG......

"The Z11 option was listed on the window sticker as 'Indy 500 Pace Car Accents' for $36.90. The SS side stripes were replaced with the orange Z28 hood and deck lid stripes. (The pace cars and the Z10's (http://www.camaros.org/69pacer.shtml#Z10) were the only non-Z28 models to use those stripes.) The Z11 package added orange D96 fender striping (not normally painted on Z28's), and also added white rocker panels (normally blacked-out on SS cars), and white rear tailpanels on the SS396 cars (normally blacked-out on big-block tailpans). Door decals were included and were shipped in the trunk; installation was at the discretion of the owner.

The required options with the Z11 package included C05 white convertible top, D80 spoilers, YA1 deluxe seatbelts, ZJ7 rally wheels, ZL2 special ducted hood, Z22 Rally Sport, Z27 Super Sport, and Z87 custom interior (orange houndstooth, code 720). Cloth seats were not otherwise available in a convertible.
The base drivetrain was the SS350 with a 3-speed manual transmission. Any other option could be added, including 396 engines and optional transmissions. Most cars were ordered with an optional transmission, most commonly a 4-speed manual or a 3-speed automatic (though both 3-speed manual and 2-speed automatic pace cars do exist). Note that console and gauges were optional, thus automatic cars can be column shift. Deluxe front shoulder seatbelts (RPO YA3) were not required, but are a somewhat common option on pace cars. Over 40% of the pace cars exported to Canada had the YA3 option [2] (http://www.camaros.org/69pacer.shtml#_ftn2) , though only 922 convertibles had them in 69. Power convertible top is another common pace car option. No documented pace car has been found with JL8 four wheel disc brakes, though a few have had the JL8 brakes added by owners."