air bag setup?

[dwalt14]

So i just started building my 71 c10. Plans are to bag it. I was planning on running the full porterbuilt setup but my buddy had been sitting on this frame for a while and gave it to me. I now how bags work but as far as the details of them not so well so any help would be appreciated. So my questions are

#1. Would it be easier to just use this frame with the rear setup and run the porterbuilt front end?

#2. What are the advantages/disadvantages of running the airbags farther up on the trailing arms as opposed to the axle?

heres a few pictures of the frame he gave me.