Diesel Loco Builder's Plates: Collecting question

I’m throwing this one out to the collectors in this forum.

I have a GMDD builder’s plate off one of the NYC/PC/CR 7400 series GP9’s built for service in Canada on the CASO between Detroit and Niagara Falls/Buffalo.

It has many many coats of paint. The top layer is CR blue. Under that is PC black, followed by NYC grey.

Do I strip the plate and laquer it so you can actually make out what is stamped on it, or do I leave that thick blob of CR blue (which is pristine) on it as-is to preserve its collectable value?

Your input is appreciated.

AJT

how did get a builder plate in the first place?