I just went through this with the 400 on my 1978 Ranchero GT. The problem is that the routing often varies within model years. You should have a VECI diagram underneath the hood somewhere that shows the correct routing for your specific car. If this is missing (like mine) was you need to find a copy of the repair manuals printed by Mitchell's. This is the only place I was able to find that actually has a compilation of the various routing options for each engine type. Check with your local public library (which is where I found mine) and see if you can make a copy. If this doesn't work email me and I can try to get you a copy via fax or snail mail.
I restored a 78 ford supercab low boy. Recently I found a set of factory high boy springs, and installed them. I'm running 33 12.50 16.6 BFG A.T. When I installed the springs it turned my steering wheel about 180 degrees. Not having a adjustable drag link, I took off the steering wheel and centered it. The truck wants to track every crack in the road, and steering is very eratic. I have replaced worn tire rod ends, tires balanced, replaced king pins etc... My thinking is that I have a steering box off center, and I don't have a way to adjust the drag link arm. I can not seem to find anyone that carries an adjustable drag link for a 3/4 ton truck. Has anyone had this problem when installing a lift kit, and what did you do to fix the problem?