welcome to the site! I have a 58 6400 2-ton as well. I drive it all over with the stock suspension and it seems to do fine. (although it has a heavy steel flatbed on it that dumps). That said, I am not sure if the fire trucks had a bit stiffer springs or not.
As far as brakes, the Hydro-vac parts can be bought, here is some info I pulled from another thread on here.
"DS in VA has done a very good job for me, 276-322-3119, Jeff is the hydrovac gentleman, very knowledgeable, reasonable prices, unlike some others."
Once you have a few more posts, you will not be moderated and be able to post links to pictures. They are not stored on this site, you need a site such as photobucket or something to host them on and then post links on this site to your photos or albums. There is a post in the "It short bus" section here that explains how to post links to pics.
Last edited by 69Cuda; 02/20/2017 5:35 PM.