Zero Ohm surface mount resistors also work really well, since they come "precut".
Just pick the right size for your board thickness and then drill the holes for a snug fit.
Put the bare board on a flat surface and load the resistors in the holes.
Solder, then flip the board and solder the other side.
I find this much nicer to work with than using wire.
Regular chip resistors might not work for your 3mm thick board, since you would need 1206 size parts and would end up with pretty fat holes. There are some MELF resistors that are round, 3.6 mm long and would fit into a >1.4mm hole which is a bit better.
MELF are a lot more expensive though, but probably still worth the time savings, compared to wires.
For standard 1.6 mm boards, 0603 resistors fit well into 1 mm holes.
0.8 mm boards can be used with 0402 resistors and 0.7 mm holes.
This method is even better if you actually need a resistor in the line and not just a jumper.