Fred, installation required fitting a pair of rivnuts into the windshield header to mount these as they are side mount units. Then a trim plate was fashioned to cover the former center mount location.
I didn't have any problem with the installation. My end was a simple stroke of signing the check to my A&P.
From Texas Aero the PN is Price:
SKU: 20-RCS-300-1-22A
Priced at $388 today.
http://www.buyplaneparts.com/cessna-150-207-side-mount-sunvisors-set-of-two-20-rcs-300-1-22a/
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