I don't think just the chamois would stay in place; and if it moved, it could be big time chafing. Look at the Sugoi ones here on TE...
Or, buy a pair of Shebeest board shorts that come with a liner. The pad is good, not too thick and you can wear the liner under other stuff. I wear the shorts all the time sans liner, for hiking, etc. I also wear them the few times I go mtb. and for doing errands.