Thanks guys, Having checked again, formate is stamped on the old ring gear, 8 1/4" dia. The replacement set is identical to the old set apart from the gear thickness so when it is installed and I make the sideways adjustment it locks up. All the bearing sizes are identical.
On the old ring gear after the numbers there is a capital A stamped within a circle.
The old ratio was 41-1, I ordered 39-1, as I had a choice. The guys at vap.inc (suppliers) say both the 41-1 and 39-1 are the same thickness. Could the heavy duty set
be for a military WC.
Have you any ideas where I can go from here??? PLEASE!!
Thank you all for your time and knowledge, Regards, Ted