I'd like to replace the original Skylark/Special 4 lug axles with a 5 x 4.75 for a better variety of wheel/tire combination. I just can't find the specs for the original axle. I've also read plenty about re-drilling the original hubs but I'm not sure if it's possible to go from 4 x 4.5 to 5 x 4.75..? I've seen many adapters but don't think I want to add the extra width. Can someone tell me what that original axle specs are? (length, spline?) OR....possible donors??