The rim does face down as shown. Then the jack base goes on first . Then the hook has a hole through the side that then slips over the stud. Then the small wing nut to hold it in place, After that is tight. the press board goes on Then the large coned washer . The large wing hut holds the pressboard down And the teeth on that large nut digs into the coned washer so you don't have to over tighten it and pull the board down.. I have seen many jack instructions that are wrong.
There are two spares for the a-bodies. 4 1/2 and 5 1/2 . The 5 1/2 must be used with disc brake cars and it sits higher then the floor. The large board is for the 4 1/2 spare it sits on the floor. If used with the 5 1/2 spare it will eventually ruin the mat. There is a small diameter board for the disc brake cars. The the mat sits on the edge of the round tire so it doesn't cut the mat. Mos all big bolt cars and small bolt disc cars came with the small round pressboard. I will be finishing a demon soon an d installing the spare. I'll get some pictures at that time.
Dis you know that the spare tire bolt reinforces the floor and holds the gas tank strap brace up so not to stretch the tub down when the tank is full hitting bumps I have seen the brace rip the floor without the brace when you drive them like you stole it.