To place the hamburger in the center of the page, I used:
.justify-content-end {
justify-content: center !important;
}
To place a wider image where the hamburger is (this placed the image over the hamburger):
.burger-icon {
width: 80px;
background: url(../images/menu-text_80x26.png) ;
cursor: pointer;
}
Since I was using a transparent image, I needed to also remove the hamburger visibility:
.burger-icon>span {
background-color: transparent;
}
Still have an issue with the offcanvas close but I'll get to that later.