I have a '97 Talon AWD and lately it's been falling out of 1st gear when I take off before the car even gets moving, on the initial clutch lift. I'm going to take it apart and try to figure out what's worn/broken but I'm wondering if this can be diagnosed before I even do that so I can order the proper parts and have minimal downtime. Is this a 2G problem as I've never seen this issue on a 1G but on 2 out of 2 2G's I've had...I've checked the shifter cables for proper throw(there's plenty)

Symptoms are as follows:

-It only pops out on the initial takeoff while the car is starting to move, never aferwards.
-I can hold extremely firm pressure on the shifter to keep it in gear but it fights me and pops out regardless resulting in grinding
-never comes out of gear if I go into it before a complete stop
-happens 4 out of 5 takeoffs (if I don't engage the gear prior to stopping)
-it goes into 1st without hanging and what seems like all the way

This is a common 2g issue. Your first gear syncro's are worn out.

add some thicker fluid for now until you can rebuild it

I got a new synchro and shift fork on the way from Jacktransmissions. I'm crossing my finger and hoping that's all it is and the intermediate shaft bearings and gear/slider/hub aren't too badly worn.

Thanks for the help!

It is likely that the thrust surface on either 1st gear or the hub (of the hub & sleeve) is worn out OR the shift fork is worn out (most likely). The synchro does not hold it in gear.
Do not hold it in gear with the shifter! You are burning up the surface on the shift fork.
Basically don't drive it. If you have to, start in 2nd.

It's almost always the shifter fork like Rob mentioned. The more you drive it, the more you can damage the expensive parts.

I suppose the dog teeth on 1st gear could be worn down too. But you'd get lots of grinding.
I'd plan on the shifter fork being worn out. It should be a close fit in the groove in the sleeve. I've seen where there was more than 1/8" play and this sort of thing was happening.