Nice to meet you again, william Slaughter
To align mainmenu to right side of your site, open the navbar.less file (templates/t3_bs3_blank), find the code:
// Navbar
// -------
.t3-navbar {
padding-left: 0;
padding-right: 0;
}
Replace with:
// Navbar
// -------
.t3-navbar {
padding-left: 0;
padding-right: 0;
float: right;
}
Check attached image to see more detail
Regards.