Lineac 4 is tiny at a mere 90 metres long
So, could possibly be mounted in the axis of a naval vessel, the sort with the power already in place for rail guns?
As for what happened to Lineac3, they're just doing all the marketing in binary, "The Lineac 1000" will sound much better than Lineac 8 when some president announces it is being deployed to quell whatever fuzzy-wuzzies we're not friends with at that particular time.