I bought this distributor, the seller claimed it's for a small block and would fit my 340(1971?) in my '70 challenger. Has petronix and was "curved". I noticed there is no o-ring or a groove for the o-ring. The numbers stamped on the body are 2875 342 9 8. Unable to find what it is from, guessing the 9 8 is a build date of sep. 1968. shaft length seem correct however the base that mounts to the intake is a larger diameter 2 3/8" as oppose of 2 1/4".