FYI for the cheap skates like me. The roof rack tracks are cheap items at the Junkyard. Look for 80's and 90's Jeep Cherokee's They have the longest tracks by far. Pretty standard on older Troopers as well but they are not nearly as long. The pictures show the roof tracks on my 88 Suburban. I used A good quality Nutsert to attache them to the body without having to drop the headliner.
The Kargo Master Serengeti had really cheesy gutter mount brackets that were easy to bend. I took some scrap 2 inch x 3/16 stock and fabbed up some brackets that allowed me to keep the rack very tight to the roof.
Got the tracks from $20 from the junkyard (bring TORX bits to get them off the Cherokee think it was a #30).
Few bucks for the Nutserts and stainless bolts I used since I already owned the tool to install them. So I was in buisness for around $30-35 as I recall.