This was a comparison done between the 2 body lift kits available from Performance accessories.
One kit was for the 1998 to 2000 Ford Ranger and the other kit is for the 2001 to 2005 Ford Ranger.
This comparason was done to try to find the reason for the $100 price difference between the 2 kits.
The findings are as follows.
Right off of the bat we spotted a big difference in the size of the gas fill tube extensions.
The extension for the 2000 is a 1/4 inch larger in diameter. The 2000's tube is 1 1/2" O.D. and the 2001's is only 1 1/4" O.D.

The next difference is with the return line for the fill tube
The extension for the 2000 is a 1/4 inch larger in diameter. The 2000's tube is 11/16" O.D. and the 2001's is only 7/16" O.D.
The next difference comes when the rear bumper brackets were put side by side.
as you can see in the pictures below, the 2001 (black) brackets are slightly larger on one side.
the bottom picture shows that all but one of the hole will potentially work.


Another difference that we noticed was that the washers sent with the 2001 kit appeared to be 3/8" larger in diameter and also 1/16" thicker, I am not sure of the reasoning because the hole was actually smaller on the 2001 washers 1/2" compared to 9/16" on the 2000 kit.
The last difference we noticed was the 2001 kit included 2 extra backing plates for the rear bumper brackets.