Mossberg 190 serial #?

[WWGunslinger]

I'm finally getting around to making a list of all my guns and their serial #s in case something bad happens.

I have a Mossberg 190 16 Ga bolt action, mag fed shotgun. I can't find a serial # on it. Any idea where it should be or if they even have one?

I got it from my grandfather (who is no longer living) so it could be a bit old.

Thanks!

Edit: Found a site that lists that the 190 series was made between 1955 and 1958. Its my understanding that before 1968, serial #s were not required, so it may not have one then.