Too bad.
It's always seemed to me that since the Japanese are firstly a RHD country, RH part numbers come before LH mates, and when they later evolve separate left and right-handed parts into a single part that fits both sides, they adopt the front code of the right handed part, and create a second five-digit suffix to create the new non-handed part. Hence the 64831-95200 RH early weatherstrip evolves into the 64831-90332 single large rear window strip used from 1965 up.
We in the USA, typically speak: "left," before "right." I guess it's the other way around for the Japanese, the Brits & Aussies, and such. Even though the 40-series was created to be built with LHD or RHD, I guess the manufacturer's preference makes the RHD driver floor area larger than that for the LHD trucks.
I also cannot see a difference necessitating a non-USA weatherstrip part from a USA sanctioned weatherstrip, unless the glass and the opening changed as well.
With all the unexplained changes and symbols, this surely becomes a project much like code-breaking.
Good-luck !