Hopefully some you folks out there will find this useful.
If you're cheap like me and can't part with (what seems) extraordinary money for an IDC punchdown tool, this might be the solution for you. I made my own punchdown tool using a piece of scrap 1/16" fiberglass PC board material and a small piece of wood for a handle. It works extremely well. The pictures below illustrate the dimensions. I used my scroll saw to accomplish the cuts needed.
Punchdown1.jpg
Punchdown2.jpg
Punchdown3.jpg
Please let me know if you have any questions.
Jeff