Just as an example:
A mechanical speedometer cable will reach because it goes from the instrument cluster to the transfer case, the same distance on any 2nd gen truck.
But in the case of your e-brake, it goes from the dash to the rear wheels. The wheelbase on a standard cab truck is 102", but an xtracab truck is 112"...so the e-brake cable won't reach, sorry. Just get a new one from the stealership, or put in a transfer-case driveline e-brake...they're alot better...
. That way later, when you do a rear disk brake conversion, you won't have to look for special calipers.
Any cable you try to buy will prolly be rusty anyway.