I want to swap an np231 front shaft to a np233c case and I am not sure where to start looking in the junk yard for what np231 case I can cross over the shaft from. I know I need to measure my chain in the np233c to see if I have a 1” or a 1 1/4” chain. Did they make 1” chains for the np231? Has anyone swapped this here? I can buy the np231 shaft and yoke from http://www.jbconversions.com for $125.00 shaft, and $60.00 for the yoke. I am just looking to save money and I have access to a junk yard.