Well, good news! I flipped the switch today and no fire or explosion. In fact, everything worked flawlessly. The light didn’t come on but I am thinking that the off the shelf bulb I got may not be the right one. We’ll see.

Based on how the wires on my SP-15 are connected, L1 and L2 are in the middle position, L1 on the left per your diagram, and T1 and T2 on the bottom, T1 on the left. But then my on-off switch has only 4 terminals and the red light is integral to the switch. Just stand back when you turn the switch on. Motor should be grounded to the line ground either directly or to a common ground in the main electrical box–then everything is grounded.