Serial Number Jx Ovulation Calendar Where Is The Serial Number Of A Mobile/manufactured Home That Was Made In The 1970's Or Early Eighties?

Where is the serial number of a mobile/manufactured home that was made in the 1970's or early eighties? - serial number jx ovulation calendar

I have no idea where you are looking for a serial number for an older model camper. I need to register for tax purposes. Is there a website that had the model I could find. This is a Redman-Fleetwood mobile home. Please help.