I have two PMW-EX1 camcorders. One was built a year later than the other so it
has a slightly glossier finish than the other. Both have a Tiffen T1 IR cut filter
and both have exactly the same settings (recalled from card) in all the
menus and the zoom, focus and aperture are all the same.

If I white balance to a card under studio lighting, one will white balance to 4700K
while the other goes to 5200K. If I do the same result with noon-day sun light outside
after stopping down and adjusting the shutter, I get roughly the same effect. One
camera balances somewhat bluer than the other.

The resulting video from the cameras doesn't quite match in terms of the whites.

Is there a recourse to get these cameras to match exactly or do they just
have fundamentally different sensors that I'm going to have to match using
PP or post production? Thanks,

I'm assuming you're A-B'ing with a good monitor, or doing a split-screen in your NLE to check the cameras. Don't make judgements based on the built-in LCD screens.
Same Firmware on both cameras?
You have both cameras set to same picture profile?
Everything in manual?
Does preset match, or is that bluer on one camera than the other?
When you white balance, what IRE is the white card?

Under most circumstances, if a basic white balance doesn't do the trick, a few minutes adjusting the picture profiles with a decent monitor that has waveform/vectorscope should get you extremely close.

I looked at both cameras on a my NLE's LCD screen and on a sony
HD CRT that has exceptional color reliability.

I just loaded firmware 1.25 on to both cameras before I synched all
of their settings with a store and recall on an SxS card.

Everything is in manual. Same zoom, same aperture. I tried futzing
with the aperture to see if that would bias the color but it didn't over
the reasonable apertures.

I did not try using the preset white balance since I have the T1 filters
on and that would yield a green picture but that
is a good idea since it isn't dependent on my white balance.

I'll try to get my vectorscope out so I can A/B in realtime. I was
recording everything and checking it on the NLE. Thanks!

Dustin, I'm unfamiliar with IR filters but I'd not try and WB or make any colour adjustments with anything that has such a dramatic effect stuck on the lens.

Sounds like you're moving in a properdirection.
At some point you might want to try a reset of settings (after you've stored your camera data from both cameras on cards.) Just to see if things are closer in their 'factory' state.
I'm also wondering how the cameras match without the filters on?
I do a fair amount of multi-camera stuff, and though a little tweaking is normal from one to the next, my experience has usually been that they are pretty close, even old EX1's and new Ex3's, (though we have to manually set the picture profiles) so it's unusual within my experience to have that much of a differential.
Sorry not to be of more help...