Here's the thread started by Casey that cover the subject.

Richard @ GDP

 

Yes I have a 06 long box,3500. Mine has two niples. One in front part of tank the other on rear part of tank. Front nipple has a line on it going somewhere. Rear nipple was exposed. Nipples are in concaves on top of tank. Concaves are deep enough that if filled with water it would submerge the nipple. theres only about 2-3 inches from tank top to box bottom, not much room. You need a flashlight and a mirror to look up in there. Not hard ,take your time you'll spot them. 1\4 inch fuel line can be pushed on nipple with one hand, no need for a clamp. Just push the line on. I bought 2 feet of line,cut some off . Used 18-20 inches. Check with the mirror to make sure you get line pushed on nipple good . Brought line over side of tank ,tucked it in behind the tank and big shield running along inside of tank. Put a $2.00 inline fuel filter on end of line, all tucked in between tank and shield. No biggy to do this.
Dodge has a recall out on the 06s,but there only putting on about a 6 inch line and NO filter. I cant see this as a good fix at all. But then they put in a new fuel filter eliment also. My dealer said my fix was better then theres and gave me the new filter to install when I needed one.
But these open elbows are on many trucks from years past that Dodge hasnt recalled.

 

Just checked my 2006 longbed (built 11/05).....both front & back vents have hoses. I will get two filters and slip them on.

 

I'll be checking mine right away. Thanx