Help with casting numbers on a 1990 360cid.

The previous owner said it was a 360 out of a 1990 ramcharger.
I am not having any luck getting any information on the block and heads. Every place I looked the casting numbers are for mid 60's through early 80's.

The heads look to be stamped 277 and 278. I'm not sure if those were the right numbers or not. I took the valve covers off to find them. Didn't see a long string of numbers like i've seen in the past on other heads.

The block is stamped on the side with 53008921 360

Here is whats on the front of the block.




From what i have read so far, one person was saying that if its a TBI motor it should have the 308 heads. Well this is TBI...



Any help would be appreciated!