First off, your welcome and thank you for helping me out as well.
I know you will have fun with it.
If in doubt of safety, I fit it till it locks up. Then hold the barrel and tip of the butt stock- where the action fits up to it- and then press underneath the receiver against my knee to see if it opens. You will usually find out pretty quick if you have enough latch engagement. But from the sounds of it, I would go out and fire it as it sounds like it fits pretty good, even though you might have a little side to side, if it's not too much, you can fix it by either shimming the forearm or use some epoxy to permanently fit the forearm spacer to the forearm. Given of course it's a wooden one.
I look forward to hearing how she shoots for you. I didn't have much time to play with it as my other project took priority.
-Aaron