How is Omega D5500/Prolab II Baseboard is Mounted?

[RedSun]

To mount the baseboard to the frame, there is a piece of black sheet metal. I've seen the metal mounted just under the column. I've also seen it mounted just under the baseboard. Both make sens to me, since the metal would protect either the baseboard, or the column.

So which way is the original way? Is that also the optimal way to mount?

[ic-racer]

The metal plate (#28) goes under the baseboard. Since the bolts come through at an angle, the plate keeps the heads from digging into the wood.