So ive experimented with the guides here cutting lenses,with some success . My emerald otts had a nasty mark on the lens ,so lens change on a budget sees mariener as a very close aftermarket emerald. Have no idea on base curves or stuff so took a chance ordered a pair and placing the ott lens on a mariener they are near perfect. Anyway, used to using dremels/ sanding so heres the result.... happy as for a display set. The colour is closest aftermarket i could find.
1st 2 pics mariener left / oem right with scratch
last pic mariener fitted
1st 2 pics mariener left / oem right with scratch
last pic mariener fitted