Their definately was a difference in the 444 and 544 front suspensions, and in fact their was a difference between the 544 B16 and B18 models. I remember this because I was surprised that a B16 owner was able to bolt 14" Ford wagon rims right on to his car, but I had to use spacers (1"!) to bolt the same spec rim onto the front of my B18 ('65). The interference on my car was on the clamp bolt for the caster/caster adjustment acme screw, I believe. These differences probably account for the discrepency in 544 turning circles. I also remember the 140's having such a tight turning circle, even better than my 544 which I thought was good enough