Hi Andy,
All I can recommend now that I understand your desire, is to place your thumb on the review button as you raise the Pen F to your eye. Once to your eye, press it. At least there is no fumbling since your thumb is already positioned.
Enjoy your Pen F. I have a silver body. It goes great and is fashionable with my silver lenses 12mm f/2, 45mm f/1.8 and 75mm f/1.8. I've had many non-photographers comment on it over the years. It is a joy to use.
James