You mentioned other engine cooling work done. Could you be specific?

What you experienced at the end of the parade, overheating and white smoke out the exhaust is not normal. If it were a 98F day, with the A/C on, going up hill, you might get close to where it was that you describe and even then that would be doubtful!

If your radiator is still has the ability to cool coolant as it did 19 years ago, your thermostat is functioning properly, fan clutch, and electric aux fans are working properly, including aux fan thermo sender, good hoses, and fan belt tight, your engine shouldn't overheat and should guage around 80C or a little above.

One or more of the items listed above may not be functioning properly, or functioning in a diminished manor. Also, if engine timing is off, or if you have improper fuel mixture adjustments, these issues can also generate higher heat and if combine with the above will occur too!