There should be key slots in the bottom of the vise, for key blocks that will drop into the table slot and (in theory) align the vise with the table travel. Assuming the slots exist, add a couple of key blocks and see (with an indicator, as described) how the vise alignment is.
Ideally, the key slots will be the same width as the table T-slot, so you'll get a snug fit all around. On my vise, the key slots are slightly narrower than the table T-slot, so I just make it a practice to push the vise forward firmly as I'm tightening it down. More fanatical people might want to make stepped keys, to fit both the key slot in the vise base and the table T-slot.
And yes,you will want a dial indicator and holder.
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