I think though that comes down to the potential fall radius from the crane - anything dropped off the tower could theoretically land within the taipan ride envelope while work is underway.
Surfrider has like 5 pieces. As they've shown, the entire track can get removed in a single night - so there's really nothing stopping them from putting it up in a night either.
If they choose to construct it after hours, then I see no reason why superman has to close for any major length of time. The slab, footers, power and comms are already there. Construction and Commissioning should be fine to do without shutting it down. Heck, they could do testing out of hours too.
Bear in mind that the primary reason rumored for this move is to provide additional capacity in a park that is temporarily lacking it - if that's true, they're going to do all that they can to keep superman open, within reason.