Nothing. The car has run for 23 years without any problems.
The original motor ran for 22 years and was never rebuilt, and is still running to this very day in my other 120y.
Only things that were changed are tyres, engine oil, points, brake pads, coolant and spark plugs.
My Rotary Datsun 120y is the best 120y in Australia.
It has been judged by Nissan Datsun Australia and is the best in all fields of body, interior, engine, stereo and wheels.
I have two 120y Datsun's and am buying a third off an old lady who also has had hers since new.
I will be restoring another 120y to make it the best 120y in the world. It will be almost original, only it will have a big V8 blown in it.
Are you sure you meant to put "1" for running costs? 1 is the most expensive? Datsun's are usually cheap to run. Anyway, you're spot on about their performance & reliability being 10/10:) - (1980 Datsun owner, UK)