I am looking for a operations manual for Lawn Genie R416LG residential sprinkler system. It was likely installed in the mid 1980s.

Did you ever find it?
I was just looking & discovered this page at Lawn Genie:
https://www.lawngeniestore.com/Comergent/en/US/adirect/toro?cmd=ToroLGOnlineOrderingPageDisplay

In the middle of the page at the bottom is a link for product manuals
Click there & scroll down till you find 416LG under consumer models
Cheers!
Joe

I used this answer & found what I was looking for. Thanks

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