I will add another comment, the 70's boats are self bailing, although when built the motors availible only weighed about 275lbs ( inline Mercs) so drop 400 on it and you will get some water coming in the scuppers when standing back there. Move a little and it drains right out, feels pretty good on your feet down here in July though
I have to use plugs on mine as I have 400 lbs of 200 Merc on it, but my 18 with a 115 Merc was fine with 3 guys standing back there, thats why we recommend 2 strokes.