transmission leak.. help!!!

the transmission in my econoline 150 6 cylinder likes to spew out a lot of fluid after driving on the highway for a little while. I had the cooling lines and the seals and gaskets checked and they are all fine. I think the problem might be the un-heatshielded catalytic converter a few inches away from the cooling lines and other parts. I'm not sure if the original heat sheild had rusted and fell off or was never there in the first place since i bought it. I'm getting the catalytic converter replaced tomorrow, is this the right move? Any help would be greatly apprectiated. If you need to know anything else feel free to ask.

thanks!!

Sounds like you are doing the right thing. An unshielded cooling line would
certainly heat up over the catalytic converter. When cat's get full of contaminants they heat up. I've seen some get so hot that they glowed cherry red at night. Make sure the tranny isn't fillled too full with fluid. Yur doing right. First things first.