What methods do you use for T- rail alignment?
I do mostly low-rise installs 2-4 floors. residential and commercial 8-12-15lb rails

methods I use: ( nothing fancy at all)
- laser to the rail with a measuring tape.
- c clamp top of the rail with a string and plumb bob, measuring tape.
- 7 ft level, cut conduit for DBG.

The better the effort, the better the result.