Extract the .rar and copy the modelspc.MDL and modelspc.Tex into "Manhunt 2/levels/A02_The_Old_House/" replace if necessary but make a security copy of the original level folder.

Very good! imagine future ideas for mods in this sense (until remaking the game)

Extract the .rar and copy the modelspc.MDL and modelspc.Tex into "Manhunt 2/levels/A02_The_Old_House/" replace if necessary but make a security copy of the original level folder.

it would be cool to put the camheads in place of the watchdogs

That was the original idea. But I placed the Hoods because replacing the Watchdogs for the Camheds would have been just replacing their heads mostly. Not their bodies.