Never found a 103 with worn guides.
I've done about 30 or more...
Replace the guide seals...use OE only.
You'll need a valve cover kit too, and replace the cam oil seal.
Replace the rotor, if you haven't already. They burn.
Being as head gasket was done, it is 'possible' new valve seal/s popped off
the guide and no longer seals.
Ask me how I know
Origonal seals go hard and no longer grip the valve stem.
Simple job....well, reasonably.
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