You cannot claim any expenses for travel to and from work, but as there would be a certain amount of 'Business Meetings' you would have to do that would be necessary for your position, you can put in some reasonable parking expenses.Of course when you are working out of base you can claim any parking expenses then as well as overnight allowances etc.
Parking expenses that you can claim should be entered as Other Business Expense.
Parking at your place of work is NOT allowed to be claimed (unless out of base).