In earlier, pre-computer, times, you looked up the part number in the parts book. Then went to the separate Price Schedule. If the part number was not in that price list, THEN you looked in the back section of the current price book (usually published quarterly) to look in the disposition list (which is where the ominous "NS1" designations also were!).
So it was . . . look for the part number, look in the current price listings, if not there, to the "back of the book" for any part number changes/NS1 designations. If a new number was found, then you looked for that number in the price list. If not there, cycle repeat. SO, in the absence of a then-current price book, you'd have to part number search EACH model year's parts book to look for the same number being used in each book.
The part number change would usually be to a later model year vehicle. In your case, to determine IF the weatherstrip did interchange with the '66 item, then you'd need to look for the same part in a '66 parts book. IF the part number was the same in both books, using the earlier '65 part number for the '66, then it was the same. Same with later model years.
Now, you have to know how the Chrysler parts numbering system "happened". First Digit is decade first used. "1" = '50s, "2" = '60s, "3" = 70s. Second Digit is the year of the decade the part was first used. "30" = 1970, "32" = '72, etc.
Best I could tell, Chrysler built ONE version of the parts book for the entire model year. Using the price schedule to hand any part number changes and such, on a quarterly basis. Any special notificaitons, mid-year or similar, would be by "Dealer Letter" . . . many of which are in Hamtramck Historical's Library section.
GM, on the other hand, built parts catalogs quarterly, which price books (with similar part number changes listed "in the back section", usually quarterly. In those quarterly parts book editions, if a part was a "new listing", it usually had an asterisk by it. In the initial edition of the new model year's book, a special "yellow page" section listed all of the new parts for that particular model year, which made it easier for parts managers to put in an initial "new part" order at that time.
I never have used the
www.mymopar.com part number search to see how it works.
As for
www.partsvoice.com, the initial version was by audio-input over phone lines. Worked pretty slick, back in the '80s! The ONE thing is that most of those parts are "for sale only", with no returns. Once you get it, it's yours. Which can also mean that any "shelf wear" or "repackaged" situation ends up in your lap. Which means that it might be what it says it is on the box, but it might be so old it's of little real value/use. If it really is what the part number says it is, that can also be questionable. So, just an advisory on these listings.
Vintage Parts International, in Beaver Falls, deals in every OEM's parts, it seems. It also seems that they have several different Internet sales portals, not being specifically for car dealerships anymore. Personally, I like dealing with them better, if possible. A lot of there stuff seems to be more later model items, too. With either vendor, the "free registration" is painless and then you can search to your heart's content.
In more recent times, it seems that both services have somewhat become overshadowed by OEM-power search engines, which dealerships and others have access to. Be that as it may. Usually, they are both listed on many of those services.
Enjoy!'
CBODY67