How do you add an aftermarket coolant resevoir???

Canton makes all aluminum stock location replacement's. What type of fan are you looking at? I have an all aluminum dual 10inch fan set up in mine and it fits just fine with my stock overflow. It flows 2X what the stock fan pulled. Look at the Be Cool website, I found it in the offroad section under f150 cooling.

Scratch that, I was going to link you to the site but it's different now and I cant find the same fan, i'll keep looking.

http://www.becool.com/#Products Thats what they have right now. Like I said i'll look for the one I have. They also have catch cans on their site.