Exactly.
I received the frame with one spacer already installed under the front removable "lug". The paclite wouldn't fit on the frame. I put two additional spacers in and went on with a little bit of "love". Though it was somewhat tight getting the upper installed, I was unhappy with that fit because it still "wiggled" a little bit at the back of the frame/upper. I then went down to two spacers. While it was a very tight fit initially, the lower and upper slid together. I didn't use a rubber mallet or bang the gun on anything, but used both my hands and kind of "squeezed" the upper backwards on to the frame while "pushing" the frame forward.
I've function tested and all works as it should. One thing to note- be damn careful putting the mainspring housing in. Make sure you do it correctly! The tolerances are so tight that it took me FOREVER to get the damn thing out and re-assembled... that's what i get for rushing the process, though.
I'm really quite happy with the fit and finish and really love the two-tone look (silver frame, black matte paclite). All that's left is to add a tritium front sight post and my critter gun is complete.
Already dispatched TONS of coons and skunks with this thing and the standard 22/45 lower. REALLY looking forward to getting out with the new set-up.