The scene in question takes place early on in the 1966 movie. when Eli Wallach’s Tuco heads to a gunsmith and assembles a firearm, before testing it out on the firing range. It turns out Wallach had no idea about guns so was told he could do what he wanted in this sequence. Nevertheless, he did receive instruction on how to disassemble and assemble a firearm.
The actor also suggested placing the Closed sign in the storekeeper’s mouth, telling him to stay quiet about robbing him. The latter’s bemused expressions throughout were genuine reactions to Wallach’s improv skills.
The Good, the Bad and the Ugly is streaming now for free on ITVX and also on Amazon Prime Video.