used a couple of different size tin cans for all the round holes,and a electric knife that is used by electricians to cut away Styrofoam in icf building blocks,and a sharp knife,and about 3 hours of figuring it all out.
its made by henry rempel here in alberta,you can order them into the USA,its rock solid,lots of adjustments,all aluminium ,light weight.very happy with it.
adjusted cheek rest and length of pull on rifle today,tomorrow go to the range and and make adjustments on 8-32 x 56 night force.then start ladder test.cant wait.