My partner and I will be flying Lufthansa from the US to Munich later this summer. The flight is booked through United, the Lufthansa operated segment is DEN-MUC. Here is the question. I can upgrade to premium economy for a reasonable price, but cannot figure out how to see a seat map of available premium economy seats prior to paying the upgrade fee. United does not show the seat map, and the Lufthansa site wants me to pay the fee prior to selecting/seeing seats. The money seems worth it if we are able to sit together, but I would like to know before purchasing the upgrade.

Does anyone have a reliable way to check the active seat map prior to purchase?