8Ks-start play and after play starts, command arm to no-mans land between disc and park position; set TF @"0" and hit "play"; servo will release arm. @"O" TF, arm should dwell at height where stylus would be just at disc height if disc was in nomansland.
If not, adjust counterweight (under black plastic cover behind tonearm) accordingly. Once done, there is no need to check calibration/TF adjuster on chrome part of arm, very accurate.
If you really MUST use a digital gauge: remove platter and see if there is enough headroom to place it there and still have it at normal disc level. Also, many of these digital scales have ferrous surfaces-watch for the possibility of the magnet in the cart sucking the cart to the scale and bottoming the cantilever! This might scew your reading and certainly isn't good for the cart; you could try putting some small plastic thing or whatever onto the scale and zeroing it before checking TF providing it stays at normal disc hight. The machine will bring the arm to the 12" LP play position and drop it because it won't be seeing the strobing of the normal platter; I've heard you shouldn't allow it to run for long in this state; perhaps someone could clear that up.
Regards, Phil