Whoever did the work machined a full aluminum bedding block. It was machined to accept the cut down magazine box. I’ll assume it was intended to be used with a glued in action as I can’t believe they intended to just use the mag box as a recoil lug.
Took a look at the bore and it was roasted. I inserted a piece of virgin 243 brass and came to the conclusion that it wasn’t a 243, more than likely it’s a 6mm Rem.
Guy that owns it has been after me for a vintage 308 Varmint take off I’ve had here that I was gonna use on my six digit 22-250. Well, he got it and this one will be rebuilt properly.