Just looked again, and as the wheel bay walls are already fitted, you won't be able to slot the wings on.
Tape one of the wings together and, if it looks like it will slot over the depth of the spars, then if you can remove the wheel bay walls, it may be possible, that's if the walls can be fitted later.
If not, then it shouldn't be too bad painting with the wings in place, just a little awkward in places. I've managed it with similar span, and larger, in even 1/48th scale, and I'm restricted with severe arthritis.