Viva, I started using 3/8 T50 staples because that is what I had on hand but they are little long. I noticed the existing fabric was stapled on with 1/4 so i did the rest of it with them.
hogasm I went with the MOOG CC880S springs and the comfort Bilstein RV shocks. It rides real nice and gave me about 1" lift. Had it aligned and it handles really well now. I scored this
Hellwig Sway Bar - 7085 - Ford E350 Cutaway Motorhome Anti-Sway Bars by Hellwig on ebay and it is going on next with a set of rear Bilstein Comfort RV shock and maybe a 1" block.
I have a set of F350 rear springs with the same dimensions as a E350 Van but they will probably end up giving me too much lift. They would be great for a 4x4 conversion. I'll probably just end up using the 1" blocks