Overheating...was it radiator sealer?

[crazypete]

I installed a second trans cooler this weekend and summarily shredded a hole in my radiator with the clamp zip-tie thingy. I got some of that black tar looking radiator sealer with the nuggets and poured it in and it stopped the leak cold. The next day, I drove it to the shop to get my 4.56's installed and noticed a bit higher temperature (1 notch above middle on the stock cluster ~220) on the highway. I was driving around today and we were covering the "n" in normal! Thats like 250-255 easy in cooler weather with rain. Since I leaked out most of my coolant, I am running almost straight water right now. So my question is..

1. Do those radiator sealant mixtures clog the radiator? Is this my problem? I'm getting some flush tommorrow

2. I have 2 trans coolers side by side covering the entire front of the radiator. Was this not a good idea? That stock AC evaporator core thing covers the entire front too, doesnt it? Do I need a gap? Theyre flush up against the radiator. (trans is ice cold! That or my temp sender doesnt belong in the TV port.)

3. I'm taching 2500-2750 on the highway. I shouldnt have cooling problems because of just that....should I? I dont mind rpms except for the heat issue.

I know the water pump is sucking because I opened the radiator hot (they really do explode if you open them! =P ) and then had to refill it with water since I squirted my coolant absolutely everywhere. When I started the car, the radiator emptied as all the water was sucked in and I had to refill it again. Mixture is almost perfect stoichiometric says my mixture guage and no vacuum leaks (20 solid hg at idle) and no reason to suspect bad timing from the great driveability. Stumped....