Head gasket-how to find the right one

  1. #1
    I'm totally confused which HG do I need because of contradicting information.

    Citroën Service (VIN search included) suggest that I should use the one with OEM 2090.Y0 (1,26mm)


    https://www.buycarparts.co.uk/elring/7017612
    fits this spec with Diameter [mm]: 73,8

    FAI Cylinder Head Gasket HG1185
    also fits OEM num but Bore is [mm]: 70

    It can't be that both fits?