In need of advice for installing the spigot filler/mag spacer in order to convert chassis from cip to la mags. I have a Remington 700 long action bravo chassis. Purchased the spigot filler/mag spacer and tried to get it installed today. Started by completely breaking down the chassis. I see how it’s supposed to fit in it but can’t seem to get it installed in the track. Measured it with a micrometer and seems to be off by 1/500th. Before I take a grinder to this thing has anyone had experience with this install?