If you had a 22 inch diameter tire that is 5 inches wide, then the kingpin offset works out to 2.95" from the center of the tire to the center of the kingpin. This allows the tire to pivot around that point.
If you have a 14 inch diameter tire that is 5 inches wide, then with the same wheel offset you would be inside the center of the contact patch and instead of pivoting around the same point, the tire will swing in an arc. This changes the relationship between the fixed rear wheels and the swinging front wheels, and not in a good way.
You need 1.88 inches to bring the 14" tires to the correct contact patch.
What you need to determine is where exactly your tires and wheels will land. The offset of the wheel is the determining factor. The 14" wheel may have a very different offset. You could be right where you need to be, or way worse.
The two possibilities for adjusting are to have either the kingpin made at a different angle to match the tire diameter and wheel offset, or change the wheel offset to match the kingpin. The offset can be changed with a spacer if you are outside the contact point. If you are inside then the wheel has to be modified or find a wheel with a different offset.