Waterford trinity mk ii heat shield

[MwCrf450r]

So I'm moving my wood stove. Currently it is in the unisulated basement and climbing up and down the stairs for minimal heat gains is getting old. Upstairs was a pellet stove so I've removed the 6"-3" adapter and plan to swap them. Unfortunately the corner I want to put the stove in is fairly tight. Manual says I can install a heat shield to shrink my clearances but that's as specific as it gets. I have found online depending on how you make your shield you can reduce clearances by 50% or about 60%? I plan on putting 1/2 cement board on some hat channel for my clearances and then tiling it. In the pictures the cardboard is roughly the size of my stove(although slightly oversized) I plan on tiling the floor roughly out to where the cough is currently for a place to put wood. But I can't come out too terribly far in front of the cough because it would intersect the door to the bedroom. So I'm trying to figure out how close I can actually put the stove to my heat shield once it's installed. Also the tiled cement board in the pic came with the house pellet stove. I've bought new tile and cement board