Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Hi Ash, the yanks used to do this mod regularly for some reason and specific filters with relif valves were available but that does not mean this is one of them. The bolt bypass rarely opens in normal use/ oil changing and at leasr thr normal hosing, bolt and fittings are the same accross all the fours so you should have spares. All you should need to do is unscrew the adaptor mate.
Solvol by the kilo then Ash and at least the missing caliper is same as 500!
That looks like a bargain Ash. Someone was trying to sell a really rough 1975 400f for £3.5k at Kempton on Saturday. Genuine barn find etc😏