This item is for both gaskets used on one rear lamp assy of the Mk2 & all Mk3 Interceptors.  Parts 43 and 38 in the picture (1 each).  Repainting the car after 20 years? Probably time to change these gaskets out for fresh foam. One gasket is fitted between the lenses and the lamp body and the other fits between the lamp body and that new paint! Don't forget to buy the seals that go all the way around your lamp before fitting to the body. And a gorgeous body it is