64.5 tailight issue...

Weird one, but all electrical issues are. When I picked up my 64 1/2 coupe in September, everything worked except fuel and temp guage. Thanks to this site I learned about the small voltage regulator on the back of the qauge cluster. All was good. It is winter here in South Dakota and the coupe stays tucked in garage until spring. This week I installed Procar Classic front seats. Love ém ! Anyway, sometime during the process I noticed I had no courtesy lights, Ya know with the doors open, no lights. I did a full lights check and I found out I have no tailights either. Been staring at schematics for about a day. Fuses "look" good but I haven't metered them. Think I'll just change all fuses (only 6 of em). But can there be any correlation between courtesy lights and tailights ? I'm wondering if it can be the light switch. I'm sure I had courtesy lights and tailights when I laid her up for storage and can't think of anything I did since. Thoughts ? Maybe some one has had a similar issue.

Actually it was an easy fix. As with many of these cars, I found that wiring under the dash is not as it came from the factory 55 years ago. Fuses "looked" good but "dome" fuse didn't not meter out.replaced that and I had courtesy lights. It also fixed tail lights. Seems odd to me that tail lights would be on that circuit, but that may have been a "work around" accomplished some time in her history. All is well again.....for now.This thing could really use a wire harness replace. I'm just not sure I'm agile enough to work under that dash for the time it would take.