I don't think .25" spacers will be a problem...but longer studs would be a good idea.
Personally since you really need to move the wheel outboard nearly .75" I would rework the axle tubes and not do spacers.
Just adding a .25" spacer will make everything work (actually it should all work fine now) but looks wise the tire is too far under the car and a wider track width doesn't hurt either. Been there done that! Remember the main reason I ordered my Fikse's!?