extra pressure on a tiny leak may have caused a one-time leak, but you'll probably see it again. Look carefully at the weep hole and the hoses, good chance you find it. Also, if you replace the water pump, it's a perfect time to replace that short hose (roughly 2" long) between the water pump and thermostat housing. The thermostat gasket gets real hard and can leak also. Use lots of penetrant on the T-stat housing bolts first.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.