As nice as it would be if he sized them I think he just got bigger rims for his f350 so he used the stock 16" tires on the trailer rims. Haha
For the holes I'm guessing they are 1 1/4" seperation just like the smaller shank. On the site it show 8 1/4" rise but I think earlier in the post you stated it was 10 1/2" rise got me a little confused.
Im thinking Since it will give me 3" more over the 5 1/4" rise shank I have now and that was the exactly how much I had to go up in height for the ball to be 1" higher the then trailer level ill be good with the bigger shank inverted using the top hole.
One question about my snap ups, I could just rest the trailer on the ball and not squat on it at all. And engage the snap ups with the bar very easily. If I jacked up the trailer only 3" I could snap them up by hand. Do I not have enough tension on the bars? Need more head tilt or less links? I think you said I want the front end to raise 1/8" to 1/4" vs un hitched right for 150# lighter? Is that correct?
Also for head tilt the teeth on the head, can do you always want teeth to be locked into teeth? Once you get to max tilt have to take out a chain link and adjust tilt back again?
Thanks for the help John
Steve