The Grand Am axles are how you get from the F23 trans splines to the Cobalt hub splines. There's no block mount carrier bearing for the Grand Am passenger side axle but it works and holds ~400whp (so far > knocks on wood). These axles are readily available from a lot of parts stores for like $70 each.... so convenience and cost is at play here also.The only thing I'm not sure about in going F23 -> F35 is the intermediate shaft, if an LAP would have the block mount for the carrier bearing and how to go from the trans splines to the hub splines.
If you wanted a carrier bearing you'd have to find some year isuzu shafts. If you figure this out lmk!