I have a Sid's 3" drop axle, new style tie rod ends, and a CPP disc setup in front with 15" wheels on my '50. The truck came to me with 235/75/15s but those hit the tie rod end when I went to put them back on, so I put a pair of 215s on the front. If I remember right, that was with the drums, and the discs went on later. The driver's side inner sidewall would occasionally kiss the tie rod end on right hand turns/sharp curves at speed, or if I let the pressure get a little low and the tire got chubby. I sanded that side of the tie rod end a bit with an angle grinder with a sanding disc to smooth the casting line out, and just lived with it for a while with no real problems, but it still made me nervous. Those tires started getting old (6 years or so on the fronts, and the whitewall was starting to crack and chip off), so I recently put 205s on the front and have no clearance issues.
As mentioned, Sid recommends bending the arms just a bit to make room.
