I agree 100% with Bosswrench about not forcing a bar to fit. First of all, ideally, there should be NO preload on a sway bar in any direction. Forcing the bar towards the frame will likely cause some binding at the outer joints as well as the central mounts. A bar should be able to move freely. For example: if you disconnect the bar end from one side of the car and at the other side you remove the shock (with spring) the suspension movement should not be affected by the bar (assuming the suspension bushing are fully compliant). If there is any drag or binding then the anti-sway bar system is not working correctly. The bar spring rate curve will be affected and inconsistent. Imagine going in and out of a binding state while moving through the suspension travel. You probable wouldn't notice it to much in a street car except in extreme cases.
Side to side bar preload will affect the spring rates at the wheels (wheel rate) which is undesirable. Maybe it's good for oval track racing? Ideally the side to side preload should be zero'd out with the car on a flat surface and loaded with driver and fluids. It's close to impossible to get it perfect on a street car but close is much better than not close.
Unfortunately the Pantera anti-sway bar system doesn't allow easy adjustment.