The aftermarket speedometers provided on many new golf carts are mounted on the steering column in plain view without having to look down at the dash or cupholders (the view of which is blocked by the steering wheel on our golf cart). The speed is in a large font on the Strikers. The speedometers also provide mileage if you choose to use that for scheduling maintenance - not all golf carts have hour meters. There is also a voltmeter; useful for monitoring the battery health.

I downloaded a "Speedometer" app on my phone - it works great. Search "Speedometer" in App store

I will add one more option, our previous cart had been modified by a previous owner to go around 26 to 27 mph. I bought a heads up speedometer that used GPS and had an alarm setting that I set for 20 mph. This kept me from speeding, but if I had an accident or was otherwise pulled over I could have been ticketed for operating an unlicensed LSV.
I still have the heads up unit, but the reflective material that is applied to the windshield could not be removed, no longer need it, new cart set for 19.9 mph.

Just check your speed with the phone app like mentioned above to make sure your only going 20 mph, and forget about it. Just a reminder if you get caught going over 20 it becomes a criminal offense which requires a court appearance, plus if your running that little motor that fast it's not going to last very long. Oh min. fine is at least $500. Check with the police if you have doubts on what the fines are.

But does a Garmin give you golf cart paths?

The units that I have do not appear to have that option, you would need to contact garmin and ask them directly.