I did not even think they made the crate motors in 1980. It's a Target Master crate that was offered through
certain retailers. Just some info if you ever see a used GM crate motor it might be older than you think.
It is odd I use to read PHR, Car Craft and Hot Rod,R&T,etc.etc religiously as a teen(1980s) and the first ad for
GM replacement crate that I remember was the very early 90s. It's not a bad thing though if you are looking
for a good block the old Mexican Crates are 4bolt mains , high in Nickel and considered fairly stout. And these
beat out many later year(back to the 80s..) blocks for the aforementioned qualities for a rebuild.
PS Another piece of info I found out is there are people looking for the older 4bbl low compression heads
for their 80s and early 90s TBI motors as they say those TBI heads are worse than anything. I sold
the heads from my motor for a bill to a guy who needed therm for 93 Tahoe interesting...