I recently replaced my entry door and now it's time to install a new
storm door.

The Question:

Does 5/4 x 4 vinyl trim have as much holding strength as wood? Can I
hang a full view storm door from it?

The Background:

Due to the gap between the jamb and the siding (3") I can't use
standard brick mold. What was used previously was some 1" (a full 1")
x ~3" wood wrapped in aluminum. The wood and alumnum are beat up and
won't be reinstalled.

Per the manufacturer, I need to use material that is 1" thick to mount
the storm door to, so I was planning on ripping down some 5/4" x 4"
vinyl trim to fill the gap and then hang the storm door from that.

(I used vinyl trim around a window I installed, and it was quite easy
to work with, but I didn't have to hang any weight off of that trim.)