try this
[x][0] onActivate -> Client -> BottomPrint("<var:br:printname>", 3, 0)
[x][0] onActivate -> Self -> VCE_modVariable("Brick", "printname", "Set", "2x2r/mintor1")
the first event line is used to tell you what the name of the print is on the brick (so you can know what to put for line 2), and the second event line changes the print on the brick.
also credit to Jam Jar for this because he showed me how to do this too a month ago