Thank for pointing out the voltage drop; I had not noticed that. I believe I need to run a bigger power supply wire to my microsquirt fuse box which also supports the coils. The fuel pumps are powered right off the battery so I doubt they experienced the same voltage drop.
TPS was recalibrated after installing the new injectors. I’ll do it again with a bit more foot pressure.
The fuel pressure drop and lean spike was scary to see afterwards. I was too low on fuel and when the tires broke loose it must have uncovered the sump. I’m glad the motor survived. New fuel sender arrives today.