Once you receive your "Worn In" guts:
My guts are set up for light sanding for a 5/8 (.625) inside diameter.
Try to fit into your call. Push hard - sometimes they feel tight, but then just work their way in. Whenever I am installing guts into a call I am not even worried about where everything is I just force them into the call to see how tight they are, then I take them back out and go from there. If they get stuck in your call - you can push the wedge with a pin or screwdriver - be careful not to damage the reed and I'm not responsible for damaged hands, limbs or missing eyes. lol - seriously, be careful.
Picture shows gap in front of the reed, make this gap as little as possible - without the reed sticking on anything as it dips down into the toneboard channel. You can hold the reed down in the channel while pushing the guts into the call. Don't fit real tight yet until you wiggle and position the toneboard until the reed moves freely up and down without sticking anywhere on the sides as it dips down. Once the gap is little to nothing and the reed doesn't stick on the sides - proceed to locking the guts into the insert. Note: there is no need to file on any edges of the reed at all - they work great and the fit around the radius on the reed is perfect. I personally file nothing, and that was the goal with these worn guts.
Always try and force the guts into the call without sanding first. Sometimes the toneboard will collapse in a little and a force fit (even if it's real tight and won't go in all the way) will push the sides back out and the guts will go ahead and loosen up just a little. Once you have forced it in. If it needs to be be sanded, sand the wedge on a flat surface - just push it down flat and shift back and forth on the sandpaper.
Picture shows approximate reed that will be left behind the wedge, then push the guts into the insert. Adjust position as needed, per your air flow.
I like tight fitting guts, so I use screwdriver type tool to push the wedge out of the call to remove the guts.