>it runs very well at idle until she gets warm and it smells like cooked ~~~~z.
It might be burning off old dirt/grease/oil that built up on the outside of the cat over time - in addition to whatever damage it can do heat wise to adjacent materials.
IR gunning the temps on both sides should go a long ways towards helping to isolate the issue(s) at least - if they both show the same/reasonable heat levels, you can start looking closer for other culprits, such as oil dripping off a leaking valve cover gasket. Keep in mind how easy it is for whatever source to supply a leak that travels and causes problems in other areas.