I finally got a pair of nice LED tail light bulbs installed in the '97 Civic, and have pics for you. I'm happy with them.
I used 7443-R45-T from SuperbrightLEDs.com, about $25 each.
They are very bright in "real life", brighter than the standard tungsten bulbs that I left installed along side for comparison. The photos don't show the actual visible brilliance compared with the surrounding area BUT you can see that the LED bulb is brighter than the tungsten next to it.
My primary aim was to reduce electrical load from the "running lights" when the headlights are on. The car runs on two deep cycle batteries, the alternator is disconnected nearly always now. So conserving electrical power is an important consideration on this car. I have a long commute without much braking so the brake light wattage - while much higher - is of less concern to me than the running lights.
For safety reasons I want both tail and brake lights to be at least as bright as regular tungsten bulbs.
For the rear, the car takes four #7443 bulbs, two on each side. These are bulbs with two brightness levels. Plus a #7440 in the center high mount brake light. A 7443 can be substituted there.
That's five bulbs for the rear, plus two in the front if I had wanted to swap those out. These bulbs are approx $25 each so swapping out all would have cost me a good chunk of change, not available right now. But I decided I could spring for two bulbs, one for each of the rear outer corner locations. I snipped the leads for the two running lights in the two inner locations. I left all the brake light leads intact. (Wattage decrease calcs at the end of this post)
These bulbs are model 7443-R45-T from SuperBrightLEDs.com. I'm happy with them. They fit nicely, both installing into the bulb holders and then into the housing.
In the photos, you can see the LED is brighter for both the brake lights and tail lights. The photos were taken in fairly bright light, so you wouldn't see the hot spot usually seen in photos of tail light bulbs, especially if taken at night. The photos' bright environment reduces the apparent brightness of the bulbs, but the effect in the photos is equal on both the LEDs and the regular bulbs. In all photos the LED is in the outer position, tungsten bulb is in the inner position.
Brake lights on. LEDs in left (outer) position:
Above: Brake lights, LEDs on left. Easily visible even in full sunlight.
Tail lights on. LEDs in left (outer) position:
Above: Tail lights, LEDs on left. Easily visible even in full sunlight.
This photo taken in shady location, shows hot spot for both bulbs. I don't think this kind of photo tells the story as well, but pics like these turn up often so I thought I'd include it. LED bulb in the left (outer) position.
Wattage Decrease Notes:
Running light wattage, tungsten:
2 front bulbs: 5W x 2 = 10W
4 rear bulbs: 8W x 4 = 32W
Total watts for running lights: 42W
That is nearly equal to one headlight bulb, which is 55-60W.
Tungsten bulbs put "out of play" by this change:
2 center bulbs disabled: -16W
2 outer bulbs replaced with LEDs: -16W
Eliminated: 32W of tungsten bulbs
Added: .3W of LEDs
(Each draws 25mA, so 50 mA for both, that's 0.3W in a 12 volt system.)
Still in play: 10W, those are the front corner running lights. I can live with that!
The brake light circuit draws 165mA per bulb. Again, this is considerably less than the 25-28W draw of the tungsten brake light bulb filament.