Thanks M.B.Doc. I contacted Bosch and they gave me a different number - MB:011 545 27 32 or Bosch: 0 280 800 448. They claimed it is what they recommend for a 3litre 1990 300te.

Anyway, the 0 280 800 322 worked for many years just fine (probably the original) and given the 0 280 800 450 succeeds this part I picked up a 0 280 800 450 on ebay - thanks again.