Hey there, So my ash tele body finally arrived and I want to start working it. Can't find grain filler around here at all. Wood filler sure, but not grain filler. Seems like it's unavailable at a lot of places on-line too unless you want a quart of the stuff for $25 or so. I just need a small amount for one guitar - is there a suitable substitute? I've seen someone mentioning wallboard compound. Is that just crazy talk? Advice please. Thanks!