The two piece rear spinner bulkhead fits onto the aft side of the metal mounting plates and is held in place with 12 AN3 bolts/flat washers/locknuts. All but 2 AN3 bolts were installed with the head forward and nuts aft. There were 2 that were too close to the hub metal to insert from the front. I called Whirlwind and they said it didn't matter what direction the bolts faced. There was also six 8/32 machine screws/nuts necessary to stiffen the two rear bulkhead halves together into one very solid piece that the spinner can be attached to.
One at a time and then they're all attached.
All bolts face aft except two. Here's one of them on the right.
I will keep a short 3/8 wrench in the Aircraft toolkit for this work.
