4 Link ? 85' C-10

Aight guys so i just joined this forum a min ago looking for some help/information. This is the first im getting in the lowrider life so i dont know too much about it. Im looking to hook up 1985 Chevrolet c-10 pickup. My buddy told me to check out suicide doors.com for info. I called them looking for a price to build a 4 link system for and i couldn't give him the right information. He needed to know how long the bars need to be and how the bags are going to be installed (whatever info is needed for them to build the 4 link). I was wondering if anyone can help me out with this if you got one of these or not.

I was also going to purchase the following:
Compressor-Oasis XD 3000 200 psi
Tank- 12 gallon 8 port
Bags- Slam specialties XS 600 psi dual port 7"
8 piece step notch kit
1/2" valves (8 pack)
1/2" air line
AVS ARC 9 Switchbox
Switchbox 9 Wire

What else will i need and will this be a proper set up for my truck. I was also told for my 600 psi i am going to need nitrogen???  looking for your help

Thanks
Wyatt  

600psi? You going to hop it?  
www.carolinadraggin.com