Marc Greenleaf Jr

Could use some help from the body work experts.
I fully removed the old trunk pan drilling out all the old welds, prior to receiving my new pan. My issue is;
The new pan does not hav a 90 degree downward bend at the very rear, where it would weld to the rear valance.
Would I simply weld the pan where it butts against the valance?
If so, should I cut off the valance where it extends past the pan or fill the holes I drilled.

Any help would be greatly appreciated, as this is my first ever project and I have no clue what I'm doing......