Oil seal seating on Sear 143.016000 ( LEV115-3600033DD)

Usually you'd want to put the sump plate on first, then put the seal over the shaft and into the sump. Tape or something over the shaft keyways won't let the sump go over the shaft, the seal will give enough for the seal to slide on.

Bert,
Yes Sir there is a lip that keeps the seal from covering the oil return hole.
Tom