I use evapo-rust only on small bolts and parts. It works, but it takes FOREVER. If you dont have several days to leave the rusty parts submerged in Evapo-rust, then you are better off sandblasting.
FWIW, I skip the primer step on small parts like support rods, cast parts, etc. Save the primer for the expensive or hard to refinish body parts. Unless, of course, you are using the primer to eliminate rust pits...which should be done with body filler followed by primer and paint.
