>Ok, I put a 50 watt bulb in to replace the stock 21 watt brake light on
>the passenger side. I also put in a new 21 watt bulb on the driver's
>side brake light. I pushed the brake pedal down and braced it in
>position so the brake lights stayed on. Then I watched the temps, back
>and forth, every 15 seconds, looking for the hottest temp spot on each
>side. I aborted the test after 4 minutes as the temps were still
>climbing and I did not want to hurt anything. I have no idea how high of
>a temp the lens can sustain without damage. I suspect that it could take
>quite a bit.

Damage will be cumulative. A tiny bit of warpage may not be noticed,
but over time will certainly be. Look at plastic fanheaters... the
(usually beige or gray) plastic eventually browns and begins to pull
back from the outlet, becoming "pretty ugly".
--
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut