i was just wondering what all is involved in shaving the drip rails on a 71 Elcameno, Is it as simple as cutting them off ant grinding the area smoth. Or will i have to weld up a seam?

You will need to weld up the GAP left behind after you shave the rails. The rails are an extentions of the inner roof support, not some piece of metal hanging out here.
It would be best to cut/remove 6in of rails then make several tack welds along the cut line. then cut another 6in making more tacks.

Thanks for the help on this it dosent seen like to big of a deal to do. For the people that have done it would you do it again?

I'm thinking of doing this to my 65 sedan but if you look REALLY close you will see what sevt_chevelle is talking about. The gap could be as much as 3/16" which would be a bear to fill. I'm going to get a section of a roof from a junker to check it out.