My '91 would start getting warm in heavy traffic. When I removed the radiator the fins were all plugged up with dirt. There wasn't a lot of leaves or other debris just a lot of dirt. I tried flushing the fins with water and blowing them out with are and that didn't make much of a difference. There was still a lot of dirt visible in the fins. I settled for a new radiator to be certain and safe.
Yesterday I was in 95 degree heat and the temp ran at about 40% on the gauge and was very steady, only going up about one needle's breadth when I got off the freeway and into stop and go traffic.
The new radiator was only about $200.00 and was well worth the piece of mind and a happy LT5.
Now if I could just figure out a rough idle...
