emmisions ysstems thru the years

[jstreeter]

Hi, I just bought a '74 california 450SL, and the famous road&track article has me confused. It claims that there is an EGR system that causes backfires on my car? looking under the hood, theres no EGR, but there is an EVAP canister and a air pump. Can anyone clear up if that was a mistake in the article, or did someone remove the EGR on my car? ( the Drivers side exh mani doesnt have a place for it)

As far as I know:
D-jet era:
72~73, '74 federal: no emmisions system (except for cold start delay valve on distrib vacuum?)
'74 CA: as above, with evap system and air pump.
'75~'76 50 state: as above, with eng room catalysts (+ EGR?)
CIS era
'77~'79: same as above, with underfloor catalyst
'80~'89: same as above, o2 sensor added

Thanks in advance!
john