"Found This Surprise In Our Front Hallway"

"I want to restore but its so much work.... Glass is mostly broken or missing. Outside is covered over with steel siding. Half of me wants to cover it back up and pretend I saw nothing. House was built in 1880. What should I do?"
I'd like to think it was used in an unsolved murder.
My grandfather brought back a "souvenir" when he popped a Jap at The Battle of Tarawa in 1943. It was a bolt action 30.06 with Japanese inscriptions carved into the stock. I remember firing it as a kid. The recoil literally knocked me on my ass.