I have a 1979 Dilly single axle tilt boat trailer. Model # is partly worn off but it appears to be 214-331-4395. It had 530-12(B) tires, has 12-4 rims, a GVWR of 1680 lbs., max. load carrying capacity of 1370 lbs. and 2-leaf springs that are 30" long and 1-3/4" wide, and appear to be the same...