I seem to have these but it is a question of finding them!
AC No.22214 User Handbook. Recovery Vehicle, Wheeled, Medium, 6x6 AEC Mk 3. Oct.1970
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.5. Auxiliary winch pulley. Jan.1972
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.6. Crane hoist lock valve. Jan.1973
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.7. Extension front propeller shaft. Jan.1973
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.8. Installation of cab heater. May 1976
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.9. Steering drag link. Jul.1979
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.10. Fitting of fog lamps. Oct.1981
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.11. Supersession of crane hydraulic pump. May 1981
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.12. Power steering, hydraulic system mod. May 1983
D 127 Recovery Vehicle, Wheeled, Medium, 10 Ton, 6x6, AEC. Mod.Instr.No.13. Installation of CLANSMAN radio. May 1984
I don't know how much commonality there is to the GS Truck
AC No.19098 Spare Parts List, Truck, 10 Ton, GS, Cargo, 6x4, AEC. Dec.1954
I assume that is just automotive only as there is a separate parts list for the GS body