Maybe you need brighter, not bigger. Are you running a 12V system? Could you try the new LED replacement bulbs? Personally, I think it's brightness that matters, not size. (LOL) Also, another (less esthetic) solution for more attention is to mount the "Third brake light" in the rear window.
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
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