The belt--Take yours off and inspect it. 50K-110K is a big jump in mileage. If you see cracks...replace it.
The PCV valve--Not a big deal, but they are what...like 2 bucks?
Idler pulleys--Check them. If they spin quietly and don't spin for a long time they are good. If they are noisy and spin freely for a few seconds...replace them.
Belt Tensioner--Check it. Same as pulleys....and Make sure when you move it up and down with the rachet that it doesn't rock in and out...if it does...replace it.
Upper Radiator hose -- can be purchased at any auto parts store..do a T-stat while your in there.
Lower Radiator hose -- will probably have to be bought at the dealer because it has the hose from the overflow bottle built into it. (I had one like that on my 00 Lightning and it was 100 bucks!!!!)
Rear End Fluid--Buy 3 quarts of dealer recommended fluid and 4oz of friction modifier. The axle won't take all 3 quarts, but close. When it leaks out the fill hole, stop...then put the plug in.
Trans--I would do a fluid and filter change. I wouldn't flush it either. Sometimes that removes sludge, or puts sludge in places where it will do more harm then where it once was!!
One last thing..(not a tune up item though)
Water Pump--I put one on ALL my 5.0L Mustangs and it really made a difference in cooling. Temp was down and the old pump had some light corrosion. I put a new on on my 2001 GT engine (that is in my 81 notch) and it was super easy and only cost me 54 bucks with a lifetime warranty!! MY 96 Cobra needs one this summer because it started leaking on me in the fall.