Rim restoration and hubcap questions

[msg]

I have been breaking down my truck and having parts sandblasted and thought the rims might need the blast but after taking them off I dont know, they arent all rusted like I thought they might be.

So I have 2 questions

1. To match the body color like I want, should I only have the front and back blasted and repaint them?
2. I wanted to go with hubcaps like these in this post but how can you measure to tell if they will fit my rims?

http://67-72chevytrucks.com/vboard/s...71#post7290971

Here is a pic of the rims, the tires that came off measure P235/75/R15