Ok let me see if I can clear this up without making thing more confusing. In Solidworks my units were inches. However, when I check the STLs in Slic3r they come up as mm. To help you make sure your parts are the correct size I can point out that the part titled 'Front_Housing' which sets the system total width and height should be 196.85mm(7.750in) wide, 127mm(5.000in) high, and 10.67mm(.420in) deep. Hope this helps.