Being fairly new to the hobby I am curious as to what your favorite period-correct accessories are on your Model T. This thread probably has been posted before and, if it has, I hope you don't mind it going again. Pictures would be great, if possible.
My favorites have to be the Rocky Mountain Brakes and the Ruckstell. Driving in Puyallup, WA, where there are lots of hills and the traffic can be crazy, both of these accessories make driving the T so much easier.
Here's 4 at once! That's a dual exhaust manifold, a Zenith S4BF carb with correct matching intake, Bosch DU-4 magneto and an accessory Bosch magneto drive unit. These really help with the zoom.
In 1979 I found my first Model T project, It it came with a pair of skies. from that time tell now
I've been searching the history of the Automobile snow attachments of the period. Although there isn't much interest by others it has been a great trip down memory lane for me.
First T as found and how I restored it.
Presuming that "period accessory" allows for a fudge factor of at least four years after a car's build-date, then my favorite accessory would be the retro-fitted self-starter in my '15 Touring. That single addition increases the utility of the car tremendously and is a traffic-safety item as well.
After that, in order of importance, come Rocky Mountain brakes and the hand-Klaxon. The winged motometer is also a cute period accessory to have.