For an extra engine crankcase breather I used a 3/8" aluminum peice for a fuel pump block off plate. I used a small boring head for a counter sink & installed an aluminum perforated piece held in w/epoxy.
Just as a side note. I finally (after about 2 years ) installed a couple of digital read outs on my old Rusnok mill. The vertical one was cheap, IIRC, $30 new, the Mitsutoyo for the horizontal I picked up @ the Pomona swap meet $20
They do not provide full travel, but for the small stuff I do on this mill will work just fine.
