I believe there have been 2 different "L89" Novas that have made the rounds in the car world...they were both 1970 model year....one was black [which I have seen] and the other was silver. Here are some links to various articles and for sale ads I found...I'm sure there are more out there if you are bored and want something to do.
If you have an L89 Nova and want to have it 'verified' and 'authenticated' please contact Ken Tibor [kwhizz] he is the leading authority on these cars and his personal knowledge is second to none
http://smclassiccars.com/chevrolet/2...num-heads.html
https://www.hemmings.com/magazine/mu...9/1643771.html
https://www.supercars.net/blog/1970-...l89-396375-hp/
https://www.mecum.com/lots/SC0513-15...olet-nova-l89/
http://findclassicars.com/chevrolet/...num-heads.html
http://topclassiccarsforsale.com/che...num-heads.html