Burb seat questions

[Bill72]

Was the second seat in a burb standard?
If not, is SPID code A53 Rear Seat the 2nd row seat or 3rd row?

Found one with SPID A53 that owner swears never had the 3rd row seat. 2nd row seat looks short on pass side for access to 3rd row seat that isn't there.
Looking at another Burb w/o the A53 code and 2nd row seat is full width.

Were there different 2nd row seats for vehicles with and without 3rd row seating?

Is the 3rd row seat the same as a Blazer rear?

These questions may not make sense, but I'm just starting to look for a Burb so it's all new to me.
Thanks.