I'm in a battle right now about fan belts too, mine blew in half down the centre last night not too far from home. Got rescued by dad, towed my broken arse back home.
The repco part they had on the book for my model was WAY out, dont trust them like sheeds says.
So far, the 2310mm I switched it over to is still too short so I'm about to re-measure and go swap again, bastard. I dont have the old belt so that just made things 5 times more annoying.
Just did a good measurement, approx 2445mm for a TJ 2001 with Aircon Compressor and Power Steering.
I drew this up then for us as a reference for this model in particular. Hopefully it helps someone at some stage.
2001 TJ Wrangler, 4.0L, Air Con, Power Steering.
(from Repco) Requires part number:
Dayco
PolyRib 6 Rib
6PK2460 (2460mm)
968K6