Trying to install XR upper driven gears, and the + / - markings have worn off the brass collar. Is there an alternate method of making sure the gear timing is correct?

Is the vertical line gone too ? The + and - are for high and low spots on the eccentric rings, if the line is still there , you should be able to judge what is high and low visually, then align a high with a low

dial indicate the gears on a lathe and mark the high and low on the gears,then align a high and low betw the gears.best way I can figure.