In this post I used a small, hobby table saw to cut the 45° bevel in the horizontal stabilizer. I left the stab in the surrounding foam board to maintain a line parallel to the saw blade, but removed the bottom few inches to adjust the saw cut.
The table saw is small so I needed to extend the fence to accommodate the the foam board that extended far beyond the table. To do that I taped a couple of yardsticks together then hot glued them to the table saw fence.
After the bevel has been cut I find it easiest to apply the tape hinge while the entire horizontal stabilizer / elevator assembly is pinned down.
To get the tape hinge centered I put a couple of pins toward the end of the stab as guides. The tape is 3/4″ wide so I put the pins in 3/8″ from the hinge line. Works great.