How to seal OEM tri fold cover

I am a new member, although I have read several threads looking for information on my new 2020 Tacoma Sport

I would like to share how I was able to get my factory trifold cover to lock down tight, as I saw that others had the same problems I was running into.

1) First thing is the cover latches have two positions, like a hood latch. If you only hear one click when you close the lid, the latch is not positioned properly. One side of the cover closest to my tailgate would click twice if I pushed down on it. I left this side alone

2) I found that the latches can be moved about 3/4" front to back. On the side of the cover that would not close tight, I found that moving the latch as far forward as possible greatly reduced the play.

3) When I took the latches off the cover, I noted that there was a shim, as I saw in other posts. I was still not satisfied with one side and experimented shimming the latch. I settled on one (1) 1/4" stainless steel flat washer between the shim and the latch. Now I get two clicks on both latches and the seal is compressed to some extent. I am happy with these results.

4) The pins that the latches engage (that are bolted to the side rails) have no adjustment. I thought about slotting the holes, but changing the latch position and adding a small shim worked well, and I left it at that.​

Thanks to those who pointed out the shim and got me going in this direction