quicksilver 270 transom problem

[katananut]

Have 1998 quicksilver 270 never had a motor on till this year. Put on a 9.8 evinrude to use with my son. Here's the problem hit a log, found out that I had dry rot around the motor mounting plate. Since it never had a motor the paint and everything else looked prefect. Any suggestions on what I can do to fix this or replace the whole transom?

Thanks