I still have the GX motor that we got from one of the engine importers in 1991, it's my spare "race" motor. The A15 motor in the car now was an import as well. I don't know the ratio of cars with import engines but I have 3 oil caps like the one pictured that came off extra motors I ended with.

I am always reminded, when posts about checking clearences come up, that I am so not an engine builder. I have more than once simply measured the bearing thickness with a mic or caliper and if it was remotely close slapped it back in. All of the bearings in the A15 are new but on the A12GX I never even looked at the bearings, after 18 seasons of abuse the rings & bore finally wore out so I relented and changed the bearings. (Don't tell anyone I actually checked them properly)

Tom