03WhiteSnake,
When you say to use the tapered one, not the flat one, are you referring to the upper strut mount bushings?
On the stock strut mount, there are two rubber bushings. One on top that is tapered (has a conical washer that is held down by the strut nut), and one on the bottom that is flat (where the strut makes contact with the lower strut mount plate).
I am assuming from your picture that you utilized the upper, tapered, bushing as your bump stop on your coilover kit?
Correct. Exactly what I did. Mine are not rubber tho, they are poly. Was night and day difference after adding these.