Did I mess my top rail??? (1 Viewer)

[joshualopez1]

I finished attaching the T Nuts and cut out my top rail. I think i might have made a mistake as i cut out my top rail to 5 1/2 Inches but the groove where my diffuser will go extends a 1/4 past the top rail due to my router cut being off… Will the 1 inch foam padding be enough to extend past the diffuser or did i ruin a sheet and have cut a new top rail???