How to change fork oil on a 2007 dana low ride

350cc in each tube for stock ride, 360cc for stiffer ride

As far as the rear suspension, a softtail won't ride a smooth as one with a swingarm, as the softtail has less travel.

On the front end, Harley has three different "thicknesses" of fork oil, light, medium, and heavy, which gives different suspension dampening.

If the front forks are too stiff, you could try a lighter fork oil.

some are not set up to service

1985 YZ250N, With the Fork off, Cap off, Spring out, take a clear school plastic ruler pore in 5W synthetic fork oil till it's 135mm from the top with the fork tube all the way down, till it just touches the ruler and the 135mm mark. Reinstall the spring, pacer, washer, Damping rod to cap, and install back in the clamps. I raced this bike for 18months in 1985/1986. Change the seals when they leak and toss the 38Kg Fork springs for 41Kg + springs to your riding weight. Over all was a good fork for it's time and Race tech can rebuild the fork and shock to your riding style and you're riding weight. I Miss the Fork flex on hard landings to my other New bikes. I still ride and Race the 85,YZ490 with the same fork.

There are three most common weights of fork oil. 5W is a light oil for a smoother ride, 10W is a heaver oil for stiffer suspension and 15W is mainly used for a stiffer ride such as racing. I have found 20W and 25W oils but they are not that common.
If you are a pleasure rider 5W or 10W would be the right oil for you. If you are always "in the twisties" and riding the limits of the bike, go with the 15W.

No the light need to be reset. Try resetting by pressing on gas pedal all the way down with ignition in ON position 3 times in 5 seconds. Good Luck