i used a sawzall, believe or not. i angled the blade back, so that tool itself was almost parallel to the floor with blade going into the glass just enough to cut. much less dust than angle grinder and just about as fast. difference, at least with mine, when/IF the blade would hit the hull i can feel it....it would kick back. the grinder wont kick....it may slow down as it meets more material, either way, it cuts it before you realize it. i just needed to get thru top layer of glass. my floor was pretty bad so prying it up after glass was cut wasnt too hard. if you kept the blade at the right angle, you can see the full length of stroke and have a good idea how far down youre cutting....ensuring minimal contact with hull. i think i tapped hull once or twice, no damage. what ever lip was left can be cut/grind away anyway you want/can. at that point you can see where hull is. with stringers....i cut thru the fillet. same idea, angle the blade back....or just stick the tip in

\ and pryed stringer up, carefully

wasnt easy to use angle grinder on stringers....especially outboard side of stringers.
keep us posted brothaman! good luck. DONT FORGET THE RESPIRATOR .....thats glass dust youd be breathing....