Specctra Autorouting power and ground

[Carl]

I have a 4 layer board, and I want layer 2 to be ground and layer 3 to be power.

What is the best way to restrict Sprecttra from routing any signals but power and ground on these layers, and keep power and ground off the external layers (except for the fanout)?

[Carl]

ok, so here's what I've come up with for this board.

I assigned all the nets but power and ground to class1.
Assigned that class to L1 and L4.

bus
fanout
selected class 1
route
clean
miter

then just added the shapes for power and ground on L2 & L3.

came out fairly decent.

Anyone have any comments or suggestions?? Again, I'm a novice on this router, and any suggestions are greatly appreciated.