From the owners manual for a 1992 GB46 Classic, Hull No. 116....
Height from DWL to top of mast..... 20' 7"
Height from DWL to top of bridge windshield (venturi).... 14' 7"
Height from DWL to top of bridge w/windshield removed.... 13' 5"
Draft..... 4' 4-1/2"
WL is obviously water line but I don't know what the D stands for.
Presumably adding the draft to the height from DWL to top of mast would give the total height of the boat from keel to masthead.