Spin,
On something like that, I would bore to what I would call a snug fit. About the tolerance Stew was on about. I would class 'snug' as a smooth sliding fit with no wobble between parts, if anything a little on the tight side but not overly so.
You have to be careful when you make sliding bushes, it is all too easy to fit them into position then find they have compressed up so they don't slide any more.
You might be better to fit the unbored bush into the fixture first, then bore it out to accept the sliding part.
John