I don't mean to sound like a cheap skate, but I really can't afford an Oscar 4-way restrictor plate. Moreso, they don't look too authentic. I was planning on designing my own hidden restrictor, but I'm interested in getting the shape and dimensions of the inner hole on the Oscar 4-way restictor as a starter. I could make a diamond, but the curve on the Oscar seems better to me.
Could someone please scan an image and post it? Thanks in advance...