The A442 was behind 1HZs. I don't think they were behind HD-Ts(edit: actually the faq/DGTLB says they were! which tells you something about their strength), but with Wholesale Auto's mods (extreme valve body, billet torque converter, AND, AND, AND having them set up the body to match the engine's shift points which is VERY IMPORTANT!!) I would not worry at all about the strength of the A440 or A442. They are insanely stout autos. If you need a good cross-cooled radiator I still have the one I ordered from Summit.
We were going a couple routes to make an auto work. I think the absolute best is either a rebuild with the above bits added from Rodney (he'll want a core in trade) and having him set it up, or the extreme rebuild with the same stuff. Really if the auto is the way you want to go (you get much better control and a higher overdrive.. and I really wanted to do it), you need to do it well. Cool it, put a temp gauge on it, have Rodney set it up and you are good to go. For some reason A440/442s are voodoo in the states and I nearly always see half-working rebuilds or people just buying used and hoping for the best.
Yoda still has the parts I got to make the HZ/A440 work. We were going to have to machine down the most minor of bumps somewhere in there (he worked it out), but it was the equivalent of grinding down a caliper to fit 3.5" backspace wheels. Super small mod to make it all work. He can get you any individual weird parts like that.
I am keeping my auto mounts in place in case I decide to head back that route, but if I get a toybox I might just take them off.
There is another trick to the HZ/auto. You will want to make your case manual shift and get rid of all the vacuum stuff so you can run your exhaust inside your frame rails. HZ exhaust is passenger, 12H-T is driver. LM did a writeup on mud about this mod and I think he's got the case sitting there ready to go (we were going to use it for mine).