Swanstone Panels: Butting ends together on same wall

I have a 66 inch bathtub; Swanstone does not make a panel that is wide enuf to cover the wall along the length of the tub. I am using two panels butted together at the centerpoint of the wall, has anyone done this???
Should the panels be butted together tightly, or should I leave a 1/8 inch or 3/16 inch gap betwwen panels to accept a bead of caulk?

There should be instructions on the Swanstone website. I specifically eschewed Swanstone because I could not get the exact size for my alcove.

OLB... you making me get out my dictionario... what's an eschew? Is it like a cashew with an esch instead of cash?

This is my first and last swanstone purchase, I will eschew ( avoid, shun, )
buying those panels again. Swanstone only offers panels for standard sized tubs, my project wouldn't have been so difficult if I had a standard 60 inch tub, I installed a 66 inch tub and later found out that custom sized panels are hard to find.

Those panels are a pain in the butt for the DIY remodeler. They are heavy, cumbersome, and hard to dry-fit into any room with less than perfect plumb and square walls. I have the panels in, applying glue and setting them in place was a piece of cake...the hard part is trying to build a shoring system to hold the panels while the glue dries. I almost had a fricking heart attack trying to shore the panels before the glue set up, all without damaging my freshly drywalled and painted walls.
I probably screwed up too, I didn't leave a wide enuf gap between the butted panels. I am going to cut (or router ) a channel between the panels that can accept a bead of caulk.

I would try a lot of things before trying to attack Swanstone with a router or something like it to enlarge a groove. I would probably start with trying to find a liquid type compound that would cure to a flexible joint in the existing groove. You might be able to inject it with a hypodermic needle and hold it in place with tape until it cures.

If there is no alternative to cutting, then I might try a thin diamond blade on a heavy duty Dremel or on a Rotozip. I would mount the tool on some kind of sliding/gliding device to help control it. If you have any groove at all you might be able to make a holder with something that runs in the groove to guide it.

panels

I would have placed the silicone sealant in the joint and then placed the second panel tight to the first one, rather than try to force it into a groove.

I think I can get a bead of silicone in the crack, I found a plastic syringe that will dispenese silicone RTV. It is about the size of the two part epoxy syringes you can buy in any hardware store.
I wish I had thought of applying the silicone into the first section edge before I butted the second panel..that is a great idea. IT is kind of like mortaring bricks together. I guess my first bathroom remodel will have its flaws. What I have learned, may help me on the next project.