We have a 87 Westie that we regularly use to transport two and occasionally three 17 foot kayaks, two plastic and one wood.

I mounted two sets of 'Side Loaders' on the pop top. The forward pair is mounted as far forward as practical. The rear pair are mounted just in front of the top's hinges. Both sets are mounted in the recesses, not the ribs.

The towers are 1a with crossbars, hullys on the rear and saddles on the front. The middle boat uses 'J' mounts from Malone of Maine.

We have many thousands of miles using these racks with no problems. It was a bit noisey at the rear where the pop top meets the roof until we added a couple of strips of the soft side velcro to the roof.

Oh, and DO NOT try to open the roof with the boats on.. My recovery has been very slow .

Dan