Serial Number advice Please !

Getting ready to pull the Trigger on a 72 Z50A-- Last thing I always ask is for the serial numbers from the engine and frame to compare the spread- There is NO Serial number evedent on the Neck of this bike- Like no where
Its a Clean well running Bike, The engine number is correct for the year. Can I stamp a serial number on it ?
Please advise !!

Replacement frames have no serial number- could be one of those. Don't know what Hondas or the states DMV official stance was on that. I suppose you could stamp one in but I'm sure it could be construed as tampering probably a federal offence. If you had the same stamps and didn't advertise it you might get away with it but the big question would be what number would actually stamp in it? What to you would be a reasonable spread? My 50 is a 5500+ between frame and engine. You could end up stamping a number in it that someone has ownership of

Is just an opinion but like @Gary said if you accidentally stamped the number of an existing bike that could be a pain for someone some day. Your in a crazy situation honestly, if it where me I would just probably leave it without a number on the frame and show off the fact that I had a replacement frame! But that’s just me and to each is own.