...if the "timing-light" indication seems to constantly "jump / wander" around at steady idle, that's a pretty good indication of timing-chain "stretch & wear."
The above can also be caused by wear in the distributor bushing or a dizzy shaft not being exactly true.
Had a Mini years ago and had something similar where the rotor plate was not square to the shaft so as it rotated it also went up and down a bit so the timing was all over the place.
Took some time to figure that one out!
The Starlets were great cars...couldn't kill 'em with a stick.
By the way Congrats to the All Blacks on their victory over the Wallaby's.
Well deserved.