TBH mate, retarded timing doesn't directly case the engine to run hot all over. Cylinder temp will be the same for example, exhaust temp will be high though.... Coolant temp will obviously go up as the high EGT will heat head up which obviously needs cooling.

Damage that can be caused by high EGT:

Burnt exhaust valves
Exhaust gasket damage
Turbo damage (although less likely imo)

I would of course change your oil due to high oil temps cause by hot turbo.

I've had coolant temps of over 100 before and haven't had any damage yet. Damage really only happens (warped heads/blocks/HGF) above 110-120 as coolant boils.

If your cars driving fine then I wouldn't worry mate

Rob,