I had trouble finding 400mm skirts for my Trident, they existed for a normal Voron, but no luck with the Trident. I cut up/pasted the original STL's and came up with these.
You will need a larger format printer than the usual 220m for the rear center skirt (267mm wide)
These aren't done super well (the models aren't perfect), but they print absolutely fine using the normal Voron print settings.
You will also have to figure out a new plan for your drill guide for the panel at the bottom of the printer, I haven't done one as of yet.
The author remixed this model.
Extended thesefrom the original 350mm Voron Trident side-skirts, to be 400mm.