I have a couple of questions regarding connecting the fixtures of a claw-foot tub to modern plumbing:

1) How do you connect the 3/8" plumbing on the claw-foot tub to modern plumbing, which is either 1/4 or 1/2"?

2) How do you cap the shower line on the faucet that previously attached to an oval shower rod, which was removed during renovation? The inner circle of this line is 3/8" and the outer circle is 3/4".