Marples 1901037 Laminate Flush Router Bit With 3/8" X 1/2", 1/4" Shank
With a $30 laminate trimmer router at Harbour Freight.
Use the old lens to cut out the new piece by holding them together with $3 spring clamps. I used 4 and moved them around as I cut the lens out. I cut out 10 in about 2 hours. I bought the acrylic
at a plastic shop for $125 for a 4x8 sheet of 3/8". Then they had some scraps for $5/lbs. Probably had less than $150 in all 10 lens's. Dow 795 for the sealant