You could always swap an LS4 from a GP GXP or 06+ Impala/Monte SS. The engines are relatively cheap, and you can get an entire donor car fairly cheap. If your going rwd there is no easy way other than buying a different car. Maybe weld an s10 chassis under there which I imagine may take quite a bit of fabricating, but at least with the s10 the 4.3 v6 is essentially a 350 missing two cylinders so it would be a fairly easy swap for the drivetrain.
With that said there were a couple LS-swapped GTP's out there back in the day. A red one & a blue one iirc. I believe both remained fwd. Idk whatever happened to them. There was also the Grand Prix G8 concept in 2000 or 2001 which had the LS1 mated to the versatrak awd system. The versatrak kept blowing up on it.
