Cheers. It's pretty easy to do - albeit time consuming and you need a steady hand.
I've made a couple, both for ED120 refractors, and I used the black plastic from one of those el cheapo display folders from Woolies. I printed the template out on paper, cut around the outside of it then stuck it onto the plastic with sticky tape and went cross-eyed cutting out all the bits using an exacto craft knife using a metal ruler as a guide.
