Ben Wampler wrote:

>  <snip>After about 5 minutes of driving, it started overheating
> again. We took it back to the shop and he welded the thermostat open,

WOW, what an inspired mechanic! Perhaps he could weld my brake calipers open so
they won't squeak.

> and took it out, it seemed a little better, but then overheated badly and we
> barely got it back (thank god the head gasket didn't blow again).
>
> We are stumped about what's causing this. I've put a crapload of money into
> this and am getting ready to set it ablaze to vent my frustrations

Keep the van but get rid of the mechanic.

> <snip>  Does the cooling system need to be bled or something?

Now why didn't your mechanic think of that?

> What does the blinking light signify?

The blinking light means that the coolant level is too low in the expansion tank
(on LHS - not the filler tank behind the license plate).

Sorry for the sarcasm but these sad stories really tick me off.
Larry