Pieter @ piconomix.com tipped us with his latest build. Check it out on the link below.
I recently had to create a programming jig for an ATmega328PB based board. 1mm diameter test pads were placed on the bottom of the PCB to give access to the ISP pins. Normally one would add two 3mm diameter holes to locate the PCB on the jig, but this PCB was too small and only had two indents on each side to keep it in place
A simple and reliable programming & test jig – [Link]