Is this your tail light? If so it's the same basic as my '38 coupe and the fix for you should be the same as mine was. No new parts required except for bulbs, just a bit of tweaking of the bracket. If the above is your tail light put a slight bend in the bracket that holds your sockets. Make the bend half way between the sockets and angle it toward the back of the housing. Bend a little at a time until you have room for a #81 bulb in the top socket (6cp) and a #1129 in the bottom socket (21cp). This will give you a 6cp tail light as opposed to the 3cp of a 12v 1157 and either a 21cp stop light (same as the 1157) or a 27cp stop light depending on whether your tail light stays on when the brakes are applied like my '38 does or if the tail light goes out.
One caveat is there IS a difference in how the housings mount so the shape at the back (mounting side) is a bit different. The car housing that I have provides enough room to make that bend. I've not adapted a truck housing bracket so while it SHOULD work there is the possibility it may not. Don't be real aggressive on your bend so that you can "un" bend it if necessary. If you decide to try that on your housing post here if it works for you and I'll write up a tech tip to submit to John and Peggy so everyone can benefit.
