Ugh, in short in I took the measurement from the nozzle dot on the paper as shown in the video to the inside face of the tower extrusion for each tower, took the average, and subtracted the measurement for each tower from that average, I'd add that value to the current delta radius correction in the EEprom. So if the average was 187.5 and tower X (A) was 187. So in the eeprom Delta Radius A(0) = 0 + .5 = .5, if it was my Y tower which measured 187.9, Delta Radius B(0) = 0 + (-.4) = -.4 . After re-leveling the center point will have moved so the I'd take measurements again. The next time if the difference between the average tower distance and the distance for that tower was say .17 then I would update the EEprom value to be Delta Radius A(0) = .5 + .17 = .67
Also, if took that tower distance average, subtracted the Horizontal Carriage offset (from the center of the screw to the face of the carriage plate), End effector offset, and the distance from the tower to the carriage plate face I measured from for the carriage offset, I would calculate my delta radius to be around ~129 (Horizontal radius in firmware). My real value to be level was 5 (+/- .1) higher than that value though. Couldn't figure out that difference though.
Hopefully that helps. If it just confuses you or makes things worse, then Gene wrote this under my login
.
edit: It seems adding in the previous correction is unnecessary. For me, adding in the previous correction led to corrections being like 3.14,3.17,2.69. If I subtracted 2.69 from those values the centering was the same. *shrug*