I’ve got a 1930s wood fire surround containing a dozen or so nails which fix multiple sections together. I have just stripped back in preparation for a new finish. I’ve discovered another piece of furniture in the same room had woodworm, so I’d like to treat the fire surround with sika sikagard woodworm treatment as a preventative measure. The treatment I bought from screwfix says it is water based. Am I likely to get rust spots showing through if I apply this to the fire surround before coating with oil and laquer? What have others used? Thanks!