There are three places to find the correct size tire for your Solara.
1. The owner's manual
2. The Sticker on the driver's side doorsill.
3. On the sidewall of the tires mounted on the car.
Tire rack.com shows two factory tire sizes 205-65-15 and 205-60-16. The latter is the most likely for the six Cylinder.
4 Cylinder: 205/65 R15 92H
size 35
the size is 14 cm but 13 cm fits also
It will be a metric size try different sizes until you find the one that fits.
The 2000 Ford Mustang with a 6 cylinder had a V6 3.8 Liter engine from the factory.
2000 for f250 has a 16 inch wheel
The factory tire size is listed on the label on the drivers door jamb
If it is the 4 cylinder, 2.2. If it is a 6 cylinder, 4.3.
16 inches wheels. Correct tire size is 225/60-16
1.6 inline 4 cylinder
Group 35 Battery Size
6 1/2"