Thanks for the Millenium Ford tip Wiswind - fantastic resource - the parts guy (Ed I think) has responded to every stupid little question I had promptly. Prices are excellent too.
I got my gasket kit (I went with the 3mm - will return it if it turns out I need a 4mm) and tore things apart this weekend. Getting to some of those intake manifold bolts was a real PITA. I was shocked but also gratified to find out that the intake manifold gasket (on the left bank) was trashed. There were pools of antifreeze all over and a thick sludge buildup everywhere else. The gasket was worse towards the front of the motor (#1 cylinder) and the center cylinder area of the gasket was pretty chewed up too. The right bank gasket wasn't too bad and I don't think there was any leaking there.
A few other things I noticed - the EGR nozzles that feed into each cylinder on the intake manifold were completely blocked (but easlily cleaned out). That explains an intermittent CEL I've been getting. Also most of the fuel injectors had a buildup of crud on them that had to be seriously affecting performance. I'm looking forward to a smooth running vehicle.
Not sure how extensive the damage to the motor has been with the coolant leak. I'll get everything back together, maybe add some oil additive to try to flush out some of that sludge and then change oil/filter and add some "Prolong" or something similar which I'm hoping could help mitigate whatever damage has been done. Anyone have any suggestions on good oil additives? Maybe I'll get another 50k out of this vehicle?