Vintage air GenIV questions

[Treetop839]

Hey guys I am doing body work on my cab and was wondering about the Vintage Air system. My cab is a heat only 1970 but I have put the ac vents in it. First question is how does the system go through the firewall( pics would be greatly appreciated)? Next question is how does the system look mounted inside the cab? Does it use the stock control knobs or what does it use. I just don't want to get all the body work done, prime and find out I have to go back to body work. Thanks!