Yep, in the manual.
My garage opener is around the same age, with the dip switches. Works good.
Basically, a series of button pushing on the UHR that coincides with how your dip switches are set on the door opener itself.
I just replaced the garage door opener at my daughter's new house because the aftermarket receiver and new remotes (older Sears unit and the previous owners didn't have the remotes) was more than a new garage opener. The receiver for her opener was $49.99 and then they needed 2 new remotes at $39.99 each. Doing the math it was $130 for the update of the old opener and the new one was on sale for $120.
I will say that the new opener is not the quality of the older unit though.