D300VS Thickened Barbell Carriages

This is a 3mm thickened version of the D300VS carriages. With the extra 3mm spacers that were required for the Tricklaser arms on the D300VS+, it puts more leverage on the carriages which warp over time. I have had CF PETG and ToughResin carrriages warp.

Instead of a 3mm spacer on the eccentric, just use a single washer. And instead of the 6mm spacer on the other two wheels use a 3mm spacer and a single washer. You may be able to get away without using washers.

These aren't tested (I'm moving to linear rails), but the changes were super trivial, so i expect them to work.

Another good mod would be to move the tensioning mechanism over to the side with the two wheels for more stability.