Duckworth wing lights question

I am installing one in each wing and have the metal work done. My question is, what is the best way to cut the thin plexi lens? If I understand the directions they say to score it with a razor and break on the mark. This seems ok on the flat part but I do not know if my hand is steady enough to go around the curve on the front. Is there a better way? Thanks in advance!

I used a cutoff wheel in a die grinder. John

or a band saw then smooth the edges

Ditto

Cut off wheel in the die grinder.

Cut-off wheel, then sand the edges to 600 finish.

Thanks for the info, I cut them today with a die grinder and cutoff wheel. After fine trimming and polishing they are done.