And the metal vent holes would still just be stuck to a plastic barrel stuck to the plastic SPAS.
That's how it is with my MiM kit, as well. The metal set included the barrel vent, the barrel mount triangle/sling attachment and the sliding stock.
I glued both halves of the SPAS cage together, and passed a both through the front triangle mount, through the cage and secured it with a nut. Then the nut was secured in place with apoxie sculpt. The I attached the vent to the cage by passing a bolt through the vent and cage and securing with a nut. Then I attached the front GL block.
The only problem with my metal set (and it may be true for all from that run, or just mine), is that the sling attachment loop, on the stock, is on the wrong side (if you're a righty). The way it's currently mounted, you'd never be able to sling the rifle and bring it to a ready position, without taking the sling off, first.
Sorry, but yes, it's a 3" long bolt or screw. Anything long enough to get through the stock and into the shroud to hold it on.
As for a sling, I attach it to the back of the shroud and the front of the SPAS cage. It's the strongest way to do it. Attaching it to the barrel and the stock will just snap it off.
I have info on that detailed in the FAQ on my website:
Rifle FAQ
My appologies, Spat. I wasn't aware of how your PR was broken down. I though it was done like the MiM kit - thompson as one piece, 2 shroud halves, 2 part spas cage, barrel, vent, shoulder stock, magazine, base plate, assorted plates, front block and pump grip.
I spend so much time looking checking out your grenades and VP70, that I never bothered to look at the rifle itself :cool
-Fred