There's smarter ways of going about it, but I just do this
txd = engineLoadTXD ( "cave.txd" )
engineImportTXD ( txd, 3964 )
col = engineLoadCOL ( "cave.col" )
engineReplaceCOL ( col, 3964 )
col = engineLoadCOL ( "cave.col" )
engineReplaceCOL ( col, 11111 )
col = engineLoadCOL ( "cave.col" )
engineReplaceCOL ( col, 22222 )
dff = engineLoadDFF ( "cave.dff", 0 )
engineReplaceModel ( dff, 3964 )
dff = engineLoadDFF ( "cavepackages.dff", 0 )
engineReplaceModel ( dff, 11111 )
dff = engineLoadDFF ( "cavemachines.dff", 0 )
engineReplaceModel ( dff, 22222 )