You couldn't be more wrong. Orientation of the shock has NO effect on valving. With a twin tube shock, if it is run upside down you will get more cavitation as the shock oil will move to the gas chamber and visa versa. The cavitation will cause more heat resulting in premature failure of seals.
This is the best commentary on the subject in this post:
Q: Can shock absorbers be mounted upside down (rod end down) and still function properly?
A. Most modern shock absorbers utilize a twin (dual) tube construction; in order to work properly the inner of the two tubes (working chamber) should stay completely filled with oil. The outer (reserve) tube contains an oil reserve along with air or a pressurized gas. If the unit is mounted inverted (rod side down), the air or gas in the outer chamber can enter the inner working chamber, resulting in poor damping performance. Therefore, twin tube shock absorbers should not be mounted upside down (or on their side), with the exception of specially designed units that incorporate a gas cell, or cellular gas material, designed to keep the gas retained in the outer reserve tube.
The best shocks are Mono Tube shocks, that is why they cost more. You can run them in any orientation and they would fix your problem.
Take a look at my Avatar; you'll see I have some experience running shocks upside down.
