Too much weight on transom?

[Big-G]

Just purchased an old West Boats 18 footer in excellent shape but the 50hp 2 stroke Yamaha lowers the stern such that the stern deck drain hole takes in water. (Other post puts weight @ 189 lbs.) The previous owner repowered in 2005 with the Yama and used a plug in the drain hole and installed a bilge pump on deck to remove water. Works okay and I've personally been off shore with previous owner without problem. Is there another way to compensate for this problem and unplug the drain hole?

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