To "rod" a radiator is a descriptive name. They unsolder the tanks from the core and run a rod thru the core flues to clean out the crud, then solder the whole thing back together. Most of the good ones put it in the crud eater tank first to soften up the crud, but hot crud eater won't get the fully blocked flues even when flushed under pressure.

My experience with aftermarket rads is bad. Flimsy when compared to the stock units.

If I had a two row core, or an unfixable three row core, the best choice is to buy a new core only, and have that installed in the quality oem original tanks. I have that on Joni now, and the aftermarket core quality was as good as the oem (I specified the best core they could get). The header plates were actually thicker than the stock, but the stock headers might have been eaten some.

The stock 87 2.6 carb radiator with a rodded core took all the turbo 2.6 could throw at it, and the needle never budged on the temp gauge from dead middle warmed up, even when towing a 3600lb boat thru the n ga mtns in o.d. in the a/t (and, yes, the turbo 4 will tow uphill in 4th gear, and you can still pass people...).

I think it's more cost efficient to even buy a junkyard rad and rod or recore than to buy a junk aftermarket rad. My best radiator shop wouldn't even fix on an aftermarket because they were too flimsy.