Ryan,
I think what you need to figure out first is what model Submariner you want. Once you have that knowledge, then you can source cases/parts to build said model. a 16800 case is slimmer and has a shallower rehaut than that of a 16610 case. An older 16610 will have different bracelet, crown and crystal, as well as bezel insert combination, than say a more modern 16610(LV for example) where the case will have no lugholes, no engraving in the rehaut and different crown setup. LEC crystal versus plain crystal, AR cyclops, versus non, flat 4 versus pointy 4 on the insert, etc.... This is of course without tackling the daunting list of dials you can use, Maxi, vs non-maxi, Swiss T <25, vs T Swiss T, etc...
Bracelet choices also vary, including the different case profiles and end link combinations.
I prefer the fit of the 16800, as it wears very comfortably, but the 16610 is my almost daily beater.