Looking at those LiteZupp lamps again, two things come to mind:
1) they seem horrendously overpriced
2) Can't tell for sure, but those do not look like high brightness LEDs like Luxeons
Again, most of the drop-in LEDs out there are not very good from a brightness perspective. I find it suspicious that they specifically do not mention brightness on their web page.
I've found a few that *might* be as bright as the stock bulbs: I've ordered a couple for testing. These use three Luxeon 1.3W LEDs and are appropriate for the rear-firing brake light. They are $17 each. I'll report back with how well they work after I test them.
http://www.superbrightleds.com/cgi-bin/ ... -x3X1W.htm
For side fire with a reflector, you'd want this other model. Again, these *might* be as bright as a stock 1156. They're $25 each and have 45 LEDs apiece. Did not order any of these, but if someone tries them let me know how they work.
http://www.superbrightleds.com/cgi-bin/ ... -x45-T.htm
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Tom
'79 TR7
'87 Alfa 75
'91 Alfa Spider