Well that answers my question if it's possible to have an LS series engine in a Roadmaster. Probably requires a complete re-design of the engine bay though... :O
Actually, from the info I gathered. GM spent the money to have the whole B-body line compatible with the LS1. They were doing the testing and getting the numbers ready for the federal regulations when the plug got pulled.
When you think about it, it makes perfect sense. The last B-body impala rolled off the assembly line in Dec. 1996. Which is technically the 1997 model year. In which the LS1 was already in the Corvette, and headed to the Camaro in 8 months.