The following is from the 1963 commercial specifications catalog
56337 D1 = Open Body
56337 D2 = Canvas Top
56337 D3 = Soft Top (Convertible)
56337 D4 = Hard Top
56337 D5 = Surrey
56437 D6 = Stripped Chassis (yes 56437 instead of 56337)
I SPECULATE the following:
8200 = Open Body
8201= Canvas Top
8202= Soft Top (Convertible)
8203=Hardtop
8204=Surrey
8205=Stripped Chassis