Short back and sides

Having assembled the z metal framework on the landscape oriented 'vertical base' (v.b.), and realised that its side to side dimension needs to be the same as the portrait oriented z-stage, I have marked out the z-stage with the same hole positions as used for the x-stage (except the pipe clip - I have to see where I can fit that afterwards). This means that I could measure directly off the x-stage to determine how far over the track-rail the stage overhangs, and use this as a guide to mark the cutting line for the left (track-rail) side of the v.b.. Then I've measured 8.5 " (= side to side of the z-stage) from there to mark the cutting line on the other side.
The plan is to cut 3.8 cm off the left and 2.7 cm off the right of the v.b. in effect making my v.b. a square.
In order to line up the edge with that of the stage, if the v.b. is a little too short in the end, I shall place the angles just outside the edge, if a little too long I'll sand a bit off.