Take it off.
Put some lead shot in it and shake vigorously.
Fill it up with vinegar and let it eat for a day.
Rinse with baking soda water.
Rinse with hot water a couple few times.
I did my C10 tank back in the summer with just vinegar water. Then the soda water rinse. Then the hot water rinse...
Its not a powerhouse, but it will be fun. I can see its not a virgin, stock engine. The block is 70s and the heads are 80s p-port. The block has been resurfaced and the #code is gone.
It will transform this old truck into quite a cruiser ๐บ๐ธ๐๐
They guy said its a runner. When he spun it over...
Crazy HUGE !!!
https://www.google.com/amp/s/www.motor1.com/news/523649/2022-chevrolet-copo-camaro-572/amp/
Of couse you could always call Steve Morris ๐คฃ๐คฃ๐๐บ๐ธ