Here is the numbers matching engine. Disregard that it had a 1969 4bbl intake swapped at some point before it was wrecked in 80's. This is the same car that made me think the L code included 4 bbl's.

Until I checked the numbers on the intake and listended to Dan, Doug and the others here in my very first thread here last year.

Look at the valve springs. They're the standard variety & the exact same as the springs on a 1970 440/350hp C Body engine I own. No mystery here. TBC...