Just fitted a kit to my drop arm in situ and I don't remember a retainer.
I did get the Britpart (yeah I know) assembly kit which comprised some very thick washers (about 10mm) and a bolt which made re-assembly a bit easier.
Ended up with an old motorcycle valve spring compressor to hold the disc in against the spring while I fitted the circlip.
Colin
'56 Series 1 with homemade welder
'65 Series IIa Dormobile
'70 SIIa GS
'76 SIII 88" (Isuzu C240)
'81 SIII FFR
'95 Defender Tanami
Motorcycles :-
Vincent Rapide, Panther M100, Norton BIG4, Electra & Navigator, Matchless G80C, Suzuki SV650
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