Fastest method would be to place a very large piece of wood or cardboard on one section's side and use a paint sprayer set to a low spray pattern, apply light coats of a rust inhibiting primer/paint. Move the board and continue. Once dried, more on to other side.
The silver aluminum paint is very thin and would work great with a sprayer.
Thick nap roller. 3/4" to 1" should work. I can picture you looking like the tin man from Wizard of Oz with a sprayer.