I've been using xray film in 3 1/4 x 4 1/4 plate holders - I put a piece of plexiglass in the holder to act as the glass plate and lay the film on top so it is nice and flat. But now I just got an old PLUS-X 518 film pack (3 1/4 x 4 1/4). I want to be prepared when I separate the unexposed film sheets from the pack -

1) is this really the same size as normal sheet film?
2) is the film "stuck" to the paper somehow?
3) does the film have the typical top-right notch or will I have to be careful to keep track of which side the emulsion is on?
4) Expired in 1955. 1st shot will be an in-camera test strip using dark slide. But do I really need to use HC110 or can I use rodinal? I don't have benzo but I have many other developer ingredients I can to the add rodinal if needed.