Ya , ToE you are rite, the J alphabet used in Sabah is for Jesselton, the previous name for K.K.
When I went to Sandakan the chap there has a Ford Capri with a J prefix.
They do add a alphabet behind the no. there too.
The single S , I think was Sandakan's early alphabet,
The SK is from Kudat district,
The L is from Labuan,
The EU, I think is from Sarawak.
That Audi 100 GLS, brings back memories, my good fren had one and I rode
in it many times, but it is a problematic car always overheating.
Only the 2nd car is rare here , it's a Vauxhall
the rest are the normal fare you will find at classic car meets.