Updated 29 June 2020: Added two new pieces, ACS Holder 2 and ACS Bushing 2. Just a modification of the originals to make it easier to maintain the 96mm spacing between rows. Testing as soon as they finish printing.

Kreg ACS Bench Dog Hole Jig. Designed this to help align my dog holes for my Paulk workbench. Tried to design something similar to the Parf Guide System, but the plastic pieces were too flexible. Had some aluminum extrusion and had a go at designing something that I could use to keep the holes aligned.

The pieces are designed to maintain the 96mm spacing between holes regardless of the side they are on. This should help to maintain alignment as you move from row to row. I've also created 'corner' pieces that would allow you to build a square to help with alignment. I did not use this. The single extrusion as shown in the picture is sufficient for my needs.

Piece to piece fit was designed to be tight to minimize wiggle. I've included links to the Fusion360 files in case you need to modify the tolerances for your machine. The tolerance for the bushing holder and bushing was very tight, a few whacks with a hammer or block of wood may be needed.

A quick rundown of how to use:

Drill first hole.
Place dog through holder and hole to position extrusion.
Place as many spacers as you have room on your extrusion, with the last piece being the Bushing holder.
Measure carefully, this will determine how rest of the holes are laid out.
Drill second hold.
Replace bushing holder with hold and drill rest of the holes between, replacing spacers with bushing holder as needed.

Links to parts purchased:

Extrusion (length to your needs)
Bushing
Bit
M5x10mm
M5 Flat T-Nut

Fusion 360 Files:

Notes: The white holders in the picture are earlier prototypes, and are just used as spacers, they should be replaced by the ACS Spacers.

Found 4 3D-models for “doghole” across many websites

IKEA Tertial - dog hole insert

Kreg ACS Bench Dog Hole Jig

MFT Square (Short)

Quick Print 20mm Bench Dog Plug Hole