I see that both are are sold for the M130 engine. How does a person know if the distributor is Grey cast iron or Light metal housing on their car? Thanks.

__________________
1970 280S M130 engine- good runner
1971 250 M130 engine- #2 rod bearing, gone
1971 280SE (blown engine,parts car)
1977 German 280S W116-only 33 years old