L e d s tail lights on my 64

bohica2xo said
No, it actually says 14.1 / 8.3 W

Wow. No surprise, I guess; the quality of Sylvania's automotive lighting line has been dropping in direct accord with their firing engineers and hiring MBAs.

Clown came back to the counter with the exact same bulbs in his hand - marked Taiwan. Two loose bulbs, no package. Printed up an invoice for $18.70

HAH! The guy oughtta be a comedian.

So now that I know they are 28w bulbs, it is a non starter anyway. With a 45c ambient before the direct sun, I don't want to pump 28w into that 46 year old plastic assembly.

That's what the stock bulbs do.

Even adding glass only saves the lens in one spot - the heat is still bottled up in there.

No -- remember the housing and reflector are metal; the heat is conducted away via the metal.

Looks like I may need to build some boards and do it right

Doing it right is beyond most people. Here is hoping you're the exception.

Another option, better and cheaper and a lot easier if you can make it fit: Pick up a pair of these and put them vertically (not slanted or tilted or rotated) behind the stock lenses. If you can't fit those, you might could fit a stack of these: