Ok hive mind:
I have a 2013 Specialized Camber FSR 29 - https://www.bicyclebluebook.com/value-guide/product/3045043 and https://media.specialized.com/support/collateral/FSR---2012-Camber-FSR-Manual.pdf (I can’t find a manual for the 2013 model year).
Is this sufficient for XTerra racing (Hopefully next year)? Are there any changes/recommendations to set it up for racing?
John
Depends on the course, but a lot of the xterra bike courses could be ridden on a cx bike so anything FS should be plenty of bike.
Yes, that bike will do fine.
I can’t think of any Xterra courses I’ve done that I could have ridden a CX bike. Perhaps they’re different in your area.
Well I didn’t say they could be easily ridden in a cx bike 
But most of them would be doable.
I wasn’t trying to be combative, I’m sure some could be ridden well with a CX bike, just not any of the ones I’ve done.
There was a local race off-road (near me) race that wasn’t Xterra that could have easily been done with a CX bike.
I’ve ridden a Camber FSR of that vintage on ‘trail centre’ mountain bike trails that are quite a bit rougher / technical than Xterra / other off-road tris.
Defo fine.
You may want to swap the tyres to something ‘quicker’ - obvs just depending on the conditions (dry or wet or mudbath from a storm). Amd what tyres you’re running right now. And whether you’re there to enjoy or want to spend more £££ on tyres to be a bit quicker.
I came to tri from mountain biking and I’ve used a way-burlier-than-needed full susser on off-road tri. It’s a disadvantage overall but i loved being able to hammer past people on the downhill sections because of a better bike and better ability to ride downhill without mincing around. (+ I’m a garbage runner anyway = will never be competitive overall - so best have fun).