I did mark them but after looking around, I think one of my old mountings might be the wrong one anyway

Found this listing on Ebay - both mountings the same part number in the advert , mine are 2 different part numbers. Been like that for years

https://www.ebay.co.uk/itm/155747195...mis&media=COPY

On mine, the longer threaded rod is reversed on the other mounting.

Confused.com