Hewland Mk. 6 bevel washers

I'm putting a new crown wheel & pinion in my Mk. 6 Hewland and am being told to consider changing out the transmission in the future because the differential parts are obsolete. I've located new differential gears and cross pin, but am unable to find the bevel washers for spider gears. John Grubb, who is working on the box, is checking with people he knows in the UK, but isn't optimistic about finding these washers. TRE said to call them on Monday to see if the size matches up with the later Mk. 9 bevel washers, but I can't believe it would be the same as the gears are different. On the TRE/Hewland diagram the washers are identified as part B18. Any help or suggestions appreciated.



Andrew