My second question is that there is a ring screwed to the outside edge of the speaker that holds down the outside edge of the accordion edge. This ring is on both of my speakers and there is no gasket. Why was the speaker made this way and how is the speaker sealed to the baffle?
Ahhhh the good ole split rim. I cannot say with all certainty, but my understanding is that this is simply the older style of the small(15 inch) cast frames, after a certain point in time(early 60's?) the casting was changed to render it a one piece assembly with heavier casting in the mounting rim area including triangular shaped gussets on the rear which more effectively precluded mounting to the front side of the baffle than the screw heads of the 2 piece design. My WAG on at least one reason for the two piece "split rim" design was to allow field replacement of the cone assembly without the use of glue or adhesive.

I don't have an answer for sealing beyond saying that the rim is a strong and true assembly, and when firmly bolted to a similar quality baffle board a fairly good seal should occur without the use of a gasket, this is just another WAG and further begs the question "at what point on the timeline did a good baffle seal become a design goal?"

Beyond a suggestion to call GPA for the low down on any differences between the 803A and 803B motors/structures, i can only parrot what i've heard/gleaned in the past and that's that they are essentially the same.

Wouldn't you want them reconed with 416 kits/parts as from my understanding 803B is essentially a 416?