Frame painting questions

[71/454]

I'm currently in the process of prepping my frame with a wire wheel for por-15. Anyone who has done this i think will agree that the novelty runs out quick. I have a few concerns though, I'm trying to be real thorough so I don't look back on this frame off and say geez i shoulda done the frame better the rust is coming thru. My trouble is this, there are a few places in between the crossmenber and the frame rail I just cant get into and secondly i was planning on brushing the por-15 on because i dont have access to a fresh air respirator, again there will be places i just cant get the por-15 to go with a brush. Is this the right way? Is there a better way? Is por-15 that tough? I'm just curious if this is what everyone else is doing, I see alot of buildup of trucks on here and just wondered what worked well for everyone else. Thanks