But Dick, aren't the locking posts on a 2 filament bulb staggered? That is, not at the same level? I didn't think a 2 filament bulb would seat in a socket designed for a single. Again, hope I'm not boring everybody, just trying to learn something here. MM Dick Benjamin wrote: > Some confusion seems to have crept in here. The two 1157s on each side > light the 6 watt filament for tail lights, and the 32 watt filament for > brake/turn lights. When the 32 watt filament is on, you cannot tell > whether or not the 6 watt filament is on, because the light difference is > very small. > > The inner two bulbs, to have the same brightness as the outer ones when only > the tail lights are on have to be 6 watt filament bulbs also. > > In this case the second filament is not used (on the 68s) so a two filament > bulb is not required in the center two positions. > > Putting a two filament bulb into a single contact socket will usually result > in both filaments lighting (depending on the particular position of the > contact button in the socket) which is probably what is wrong with Mark's > car. > > Dick Benjamin