Parts such as the Water Pump & Adapter: Washer,spr.loc 3/8, Washer, Spring Lock, Shift Rod Guide, Sponge, Insert, Cartridge are included in the 40s/50es(j-p)/90/115/200etl(h-p) 1986-1991 Water Pump & Adapter parts fiche.
This Adapter Plate, (z) is the most expensive of the items that make up this Water Pump & Adapter assembly.
With four applications this Bolt, 10 X 35mm is the most specified part.