What sealant between transom boards/transom?

Finally got the plywood all sealed up with Spar, got the holes cleaned up, transom cleaned up, and all the stainless hardware purchased.

I'm ready to mount the boards back onto the boat, but was wondering what to use for a sealant around where the bolts pass through the transom. The boards I took off were put there from the factory back in the 50's, and whatever they used was black and a pain in the rear to strip off with the wire brush.

I'd rather not make it permanent, as I hope to Flex Steel the boat next summer and I'd hate to have to ruin the boards to get everything apart to do it all over again after the paint.

Any ideas?

C

If your going to pull it apart next summer I'd just use silicone chalk.

I'd use GE 4200.It is designed to be under water & is removable.

Since the transom is being bolted to the aluminum, you are only sealing the holes from water. So any thing you prefer to use for wealing water is fine. I usually use silicone.