I have the stainless steel FRPP shorties in my 740, and as instructed by Ross Converse, I put a dent in the header with a ball peen hammer where it meets the steering shaft. This does not give enough clearance-well, maybe if you hammer it flat. As Michael mentioned, I too had the header modified by cutting it off at the flange, then rewelding the now shortened tubes to the flange.
I found I had to go to hex head bolts because I couln't get the 12 point socket over some of the bolts, and had to reshape the dipstick(could use Lokar I guess)
If I could do it all over, I would rather have taken the modify the header approach(or custom longtubes) on the right side as well. I know many will disagree with me, but I just never liked the idea of cutting the frame rail and hammering it over. I really got nervous when I was told I could use JB Weld on it;I just used chewing gum instead(just kidding).