Hi Steve
Because of the money involved if it is not right, and also the possible implications if it all goes wrong, and the peace of mind when you are thinking about it when you are trying to sleep, and the short amount of time it will take, I personally would check them. Because of the engine noise, it is not always possible to hear every little noise. I wouldn't bother changing the o-rings as they will probably be OK, and if one did decide to leak, then that one can be changed.
Undo the cap head screw, turn the prop until both valves are closed and then push on the pushrod end of the rocker arm with the handle of a hammer or a piece of wood for a couple of seconds. I can almost guarantee they won't move, but it is worth checking.
It will take you about 5 mins to do all 4, and that is taking your time.
I agree with Bill that you probably won't have damaged any of the valve train, but I would check the hydraulic tappets are purged.
Cheers Mark
