In high stress areas, it's very common to web both sided of the spar. Even if the plans don't call for it, I've made it a habit and have NEVER (30Years) had a wing failure. Rather than damage what you have already completed, cut some pieces of lite ply to fit over the existing webs. It won't be quite as good as the webbing on both sides, but I don't believe you're going to have any problems. 1/16" lite ply should do it.

Make sure that the additional webs fit tight from rib to rib.