I would paint the rear wheel bolts aluminum which is closer to the original color that silver mist gray. The front tires are 16x6.50-8. Rears are 23x8.50-12. There were two different battery hold downs used on the 10 and 12 tractors. The earlier ones used a 1/4 rod with a hook on the end of it and threaded on the other end. There were holes in the back bottom corner of the battery box for these rods to hook into. An angle iron type strap went on the outside top edge of the battery and these rods went up through this strap with a 9/32" ID hole, 5/8" OD size and 1/16" thick. 1/4" flat washers (basically 1/4" flat washers) and 1/4" NC self locking nuts were used to tighten it down.
Tractors with the other style hold down had 1/4" rods that stuck up at the back corners of the battery box. A special flat hold down was used with a lip extending up on one side and one extending down on the other. The strap sat on the top back edge of the battery with the downward lip sliding down on the back of the battery. Same 1/4" flat washer and 1/4" NC self locking nuts were used.
The wheels were different colors depending on the year of the tractor. The earlier models had aluminum color rims with red centers. Same with the fronts (the center caps were aluminum colored). Later models from 1969 and up were painted entirely silver mist gray. By the way, the chassis is not flint gray but flint gray METALLIC. If you buy the flint gray paint it is not the same color as the flint metallic gray. The flint gray without the metallic looks dull and plain in comparison. The paint code is M1025. It is also available from TISCO company.
Hope this information is helpful.