Thank you for the tip, Joe. I pulled the top right side bulb, but it made no difference. I fiddled around with the 1158 bulbs in both sockets, checking for clean contacts and solid wire connections. Still no brake light on the right side, but now I notice another issue. The top and bottom bulbs blink together like they do on the left side but when I turn on the headlights, the top and bottom right side bulbs alternate blinking. The left side bulbs still blink together. I don't know if it matters but the right side bulbs blink maybe 50% faster than the left side. I think the issue runs deep into the wiring. I am going to dive under the dash and start checking and cleaning more contacts and wires, especially the directional signal plug connector. I've been referring to the 1953 and 1954 Manhattan schematics I have. The '53 shows 1 bulb and the '54 shows 3 bulbs. I split the difference for my late Special!