I saw an 01 halfton with an SSS wheel and he said it was a direct swap
THAT is not a direct swap. 2003+ half tons are dual-stage airbags. 2002 and older half tons are single-stage airbags (like all HD trucks).
So he must have put a silverado SS steering wheel in his 01 half ton, and then used a (single-stage) airbag from a 2003+ HD truck.
Which probably isnt the greatest idea. Airbag deployment timing and deployment force are obviously very specifically calibrated values and the airbag inflator modules are designed accordingly with specific amounts of propellant etc.
All 2001+ HD single-stage airbags are fairly depowered (as far as how fast/hard they inflate) compared to the half ton airbags.
This is due to the generally lower crash impulse and "g-forces" that you would experience in crashing an HD truck (because they are heavier; they decelerate slower in a crash, so you dont need as forceful/fast a deployment to provide the proper amount of supplemental restraint)
One of the head engineers at GM Safety/Restraints told me a while back that the HD single-stage airbag deployment force is comparable to only the first deployment stage (lower deployment force) of a 2003+ half ton airbag.
2002 and older half ton single stage airbags are closer to a 2003+ truck blowing both stages (higher deployment force).
So if you are in a moderate-to-severe crash in a 2002 or older half ton that has any single-stage HD airbag in it, you might not get enough supplemental restraint (from the depowered single-stage HD bag), and could bottom out the bag, smacking your head on the steering wheel......
Its your decision
Ben