We have a wheelhouse cruiser, fantastic this time of year but in the summer it's hot hot hot! We've put blinds in but with two side opening doors there just isn't enough ventilation, plus it leaves you feeling a bit cut off from the action on the deck and little access to trimming lines. Having sourced some great value Vetus hatches I thought about putting one in the central window front and rear (3 big windows facing fore and aft). The glass is toughened though so no chance of cutting, it will mean replacing with Perspex. The question is, with the windows being near vertical and almost no overhang to protect them, will it be possible to get get a watertight seal between the hatch and the Perspex?