Building a '48 F1 streetrod. I'm using the 1948 frame, but will use a 1968 F100 9" rearend assembly. The width is correct and the spring perches are in the right place to bolt up to the '48 frame. The '68 rearend I'm using came to me with 28 spline axles. Would like to know if there are any 1957 to 1972 F-100 rear axles with 31 splines available. Any help would be greatly appreciated.