Not sure how you’d properly seat it if not. But hey, it’s not that big a deal. Your timing doesn’t need to change as you’ll lock the IP pump. It’ll allow you to inspect several things, get fresh oil, coolant… routine maintenance stuff. Rest is just bolts…
Now that I think about it I don’t think you have to lock the IP at all
and inspect your front pulley—they are often knackered from the woodruff key slamming into its key channel putting a notch in the channel (prior to breaking the nose of the pulley). This is why it’s so important to have such a high torque on the crankshaft pulley bolt to prevent this slight slippage that grows more and more.