For most trains, you can select your seat or state your preferences directly from the sj.se website.

Single seats in second class are probably not possible, it’s almost always 2x2 seating. First class regularly has 1X2 seating.

Reserve your seat here: https://www.sj.se/en/kop-resa/sok/resa/fran-station/till-station/datum

Make sure to add your interrail/eurail pass to your passenger details, under SJ Prio/period ticket. Otherwise you pay full price. They ask a code just enter “E1111111 or I1111111” (any random number is okay anyway).

I have selected 1st class refundable.  The only options under select seat is (1) best available seat (2) seat requirements (with table, without, etc.) and placement (window, isle, etc.) (3) Request specific seat (which is not allowed for more than 1 reservation) None show a map or give the option to sit together.  Any ideas?

The reservation should cost 68 SEK for two, anything more means you probably bought an ordinary ticket.

Your best option is “Seat with table”, and window for placement.

I purchased seats and went on the chat and had them changed to what we wanted.