I set it at 2000, which I think it's well worth ? I don't know, maybe I'm nuts.
Give it another try and see, it can't hurt. I think $2000.00 might be too high a price without the original engine assembly code and partial vin stamped on the engine pad to show it was an original Z/28 engine. The only part on your engine that is unique to the Z/28 is the crankshaft as the 3914678 block was used in all '68 Camaro small blocks. Good luck with the sale!