I bought a Bartz engine from Jim Crittenden in the late 70's or so and had it rebuilt and installed in my '69 A-Sedan Camaro.
We subsequently used that engine (with heads updated by Rehr-Morrison's Lee Shepherd) in both our '82-bodied C3-chassised GT1 Corvette, as well as in our '86-bodied tube frame Trans Am spec Camaro. Heads eventually acquired so many cracks in the valve seats that they were no longer servicable.
Block was still in use in 1993 when my partner and I sold the Camaro.