Hello again.
Just make sure the cooling system is at its best. You may want to invest in an aftermarket temperature gauge so that you can know if half temp is even hot. These old standard gauges do not indicate actual temperature, and after 30 years the sender unit in the engine can become slow to react or ineffective, or misread all together.
Perhaps you can fit an inline temperature sensor in the side of the hotter top radiator hose and see exactly how hot the water gets at its hottest. Anything under 90 degrees Celsius could be considered normal, generally it should stay around the same temperature as your thermostat opens, give or take 5 degrees.
There really is no accurate way of assessing any issue unless you have an accurate temperature reading.