ok cool... The color pic is a my first proxy sub (low rez not smoothed)...and I was testing caustic's, underwater etc... Note the slots along side the upper part of the hull... This is one of many slots, circular holes, etc that need to go into the model. I am looking for the best method to create all these details. The previous methods, booleans and extruding either played too much havoc with the geometry, or was too time consuming doing extrusions and fixing the geometry for each detail. I am starting the 3rd sub...so in the pic that follows I hope you can see the idea better. I created an extruded piece for the slots... I am trying to ascertain how I can attach these and other separate extrusions and or planes into the hull, deck or sail(conning tower)... If you look at the top view ortho sub deck I think you will get the idea as all the dots are more slots on the deck... The reason I think this is a reasonable idea is the geometry of the extruded piece is ready for smoothing or subdivision. So I wouldn't have to go and fix each one... Hopefully that helps... thx...