"WP27 61 3 43"

The 5th digit should be a letter. If it is a "G", I'm not 100% sure about this but I think it might be a 340. I am certain that "F" was 318 in 1969.

27= Convertable

Also:
WP = Coronet 440 (the model not the engine) WS would be R/T, WH would be plain Coronet and WM would be Super Bee.

That's all I can remember off the top of my head.