This is a damn hard task working out the proposed lineup I reckon. I think the best way is to work out proposed min/max power for V8 and the same for the 6, then slot the cars in. So lets have a go...
min/max for V8..................220kw-----300+kW (with 1 exception

)
Now V8 models that fit in here would be..
AV XR8..............................240kW
AV LE XR8.........................260kW (FTE)
AV TE/TS/TL......................275kW (FTE)
AV GT...............................310kW (FTE)
Limited AV GTHO..............350kW

(FTE)
Now min/max for 6...........170kW-----220kW (with 1 exception)
AV XR6.............................190kW
AV XR6T............................220kW
AV XR6FteT.......................240kW (FTE)
Well something like that anyway