OK, the last version turned out being perfect in every way.
Here's my svg for anyone that is interested. To be milled with a 1/8" or 3mm bit.
A video is on the way laying out the whole process.
I use 6mm dowels, so US people will have to change the hole sizes to match their dowel diameter. For 6mm dowels, the tolerances are press-fit, but a bit of glue is never a bad thing.
Note that I 3D-carve the grips, but the outlines are included in the svg.
Be sure to cut along grain, for less friction on the slide. Also shave off a hair of he trigger's total thickness.