Let’s do an analysis of the screw used to retain the windshield washer “T” –
1 We have two pictures of the screw, the first without an external tooth lock washer, the second with.
2 We have to assume that the two screws have the same thread diameter primarily to fit the mounting hole in the “T”. That would be a size 8.
3 Neither picture defines the screw diameter, pitch, tip type or length.
4 As the “T” is attached to the cowl sheet metal, we must assume a sheet metal screw is used.
5 There is only one sheet metal screw this size shown in the AMK Guide to Ford Fasteners. It is only used in 64-66 glove box applications, 374565-S7/8. No other years use this screw. No other size external tooth lock washer sheet metal screw is documented.
6 Both the 67 and 68 Body Assembly Manuals call out 373611-S2 for the application in question. It does not use an external tooth lock washer.
7 Both the 67 and 68 Body Assembly Manuals call out 373611-S2 to attach the nozzles to the cowl.
8 Assuming the same assembly line station installs all the windshield washer hoses, nozzles and “T”, the same screw would be used in all three places as it is documented, mainly for ease of assembly. (Note: the 67 manual calls for two screws in the Bill of Materials section although there are three shown on the drawing. It is corrected in 68.)
You can make you own conclusion but 373611-S2 seems to be the correct screw for this application.
Jim