Need furnace and A/C info please

I came across a Weather King forced air furnace and A/c Unit today. I can’t find any info as to age of either of these units. Any help would be greatly appreciated.

Furnace ser# CN3D102 F2787 1647

A/C ser# 288022 57195

I am thinking 1987-88. The home was built in 1988.
Thanks in advance!

Looks like the Weather King may be similar to:

Rheem & Rudd: in the middle of the serial number will be a letter “F” the following four numbers are the week and year.

…so your thought on ages are probably accurate given the age of the house.

Furnace 1987, A/C 1988

Thank you guys !!