Need recommendation for a good mastic glue

I am looking for a good mastic trowel-on glue to attach wood boards about 5" wide, to plywood. This is to make "barn" style doors, they will be using inside a home, so there will be no rain / sun to deal with.
I will secure the boards with a 23 gauge pin gun too.

thanks, Mark

This stuff is available at a Big Box store near me. Has anyone tried it?

Attachment 433175

PL premium would work.

Is there going to be a problem here with wood movement?

I've used PL400 for that very thing, worked fine.

Thanks for your suggestions on using PL adhesive.
Matt, there should be minimal issues around wood movement. However, I have quite a bit to do so I'm looking for a gallon mastic at least, not tubes.

I think this might work. The specifications say it allows for wood movement, never a bad thing.
Attachment 433204

I don't understand going to the trouble to trowel it on. One of the PL's comes in clear. I'd use that, and the large caulking tube size if you already have a gun for that size, or the regular size. The adhesive doesn't have to cover the whole backs of the boards.