The additional Plus in Wa. is
You are NOT required to run a matching front plate, You can omit or run a typical promotional plate of your choosing.
BLP 777
"Blip- Triple Seven" aka Lucky Dog.
This is the # the car was sold on & matches the First registration dated May 1968
(26, Dec 1967 Build & Ship Date)
"B" plate was for Pierce County (aka Tacoma)