View attachment 148072
J-36 is not super long, maybe 0.5 to 1 m longer than J-20. So when a tandem twin seat J20s is compared with it, it's obvious the canopy is much longer when in tandem configuration. Leading to the conclusion that the J-36 indeed does not likely have tandem seating. Which again leads to the strong possibility of side by side seating.
Even if one believes J-36 is 2-3 m longer than J20, the canopy length difference isn't that great, with the J20S one still being visibly longer.