I wanted to piggyback on this thread - I just booked a trip to Uruguay on AA with the last leg on GOL to/from GRU. The AA international segments are in premium economy.

Do I still not get to choose seats on GOL? I went to the website, pulled up my flight reservation just fine, but there was no option to select seats. This was the Portuguese site, if that makes a difference.

I realize this is technically an LCC so it may not be possible at all, but I figured that since this a higher fare class on the booking carrier (AA), maybe some of those benefits carry over to the partner.