Editing Identifying Chevy engines

Hello Bow tie friends.

    I am curious if anyone may be able to shed some light on some I.D. markings on the pan rail of a 67 chevy 302 short block that I purchased several years ago.  A friend of mine who was into circle track racing came accross an engine and notified me because I was restoring a 68 Camaro Z/28.  He told me that the engine he had found was an original 67 DZ 302 engine and that he thought I should put it in my Z/28.  I purchased the engine from him minus the 2.02 heads for $1200.00.  The short block was fresh at that time with 12to1 pistons, pink rods, steel crank, double roller timing set up and a high performance Comp Cams cam in it.  When I removed the oil pan there was a stamp on the pan rail that had a block # followed by 1967 302 C.I.
290 H.P.

My question is, is there any way to verify that this is a true 302 engine?  I have since studied up on the 67 Z/28 Camaro's and found that there were only 602 Z/28's manufactured in 1967 making this very rare if it is a true 67 302.  It does have the small journal which would indicate 67 but I don't know how to verify what its origin was.  Any help would be greatly appreciated as I intend to sell this engine and do not want to mis-represent it in any way.  Thanks in advance for your responses.
                                                Raycrx