Changing transmission cooler o-rings--any tips?

[JTis]

Hey folks,

After seeing small puddles of coolant appearing under my 4.6 at various times with no real rhyme or reason, I finally got around to lifting the truck up and taking off the splash guard this weekend to investigate.

Luckily I noticed blue crusty buildup around both the black plastic intake and exit ports of the transmission cooler....seems pretty clear that the o-rings inside are bad so I have a couple ordered right now and plan to replace this weekend.

That leads me to my question---anyone done this job personally? From searching the threads, I can see where several have had the job done, but I haven't really seen it detailed in a DIY type post. If you've done it, a few questions:

1) How hard is it to get the cooler off the radiator? It looks to me like there's one clamp holding it on---unfortunately the business end of the clamp is out of sight on the topside of the cooler, but I think I can manage it by feel. Any tricks or "don't do X or you'll break the clamp" things I should know?

2) I'm guessing that since this connection is at the very bottom of the radiator, I'm going to basically be draining the radiator when I remove the cooler. Should I just drain the radiator through the drain valve before removing the cooler, or is it just 6 on one hand/ half-dozen on the other?

3) Should I be worried about having a bubble in the system when I refill the coolant? Any tips on how to avoid that?

Obviously anything else you think I should know would be appreciated---this looks like a simple enough job---I just want to make sure I'm not missing anything obvious.

Thanks!