You’re right, thanks for correcting me, anywhere I wrote “original 1987x” I was referring to the 1987.
It’s the first coupling capacitor on the bright channel. Original 1987 spec should be 2n2F but the reissue 1987x has a 22nF. Marshall have often done the same on their 1959 reissues too. Note there is some variation in these parts both on original 1987s and reportedly also some eras of reissue 1987x, so you’ll have to check and see.