They are kinda of a pain to get at with the fenders on but can be done by removing the fender splash shields. Here's you a pic of where they are. They are the tunnel shape openings.
Lotsa luck getting 45 years worth of pine needles, leaves and other composted guck out thru those weep holes.
I ended up having to open the heater box and removing the driver's side air box, reach up inside and pull out what I could (without slicing an artery on the sharp edges!). Combination of compressed air & vacuum cleaner to get out more, then go for a drive and let the wind blow 10 lb of crumbs into the car.
Repeat procedure as many times as necessary.
Hopefully, you didn't fry the gauges when the voltage limiter failed.