Transom hole help, 76 Sceptre 23 PLEASE !!!!!

[PJMurray92]

I bought a 1976 Potter Hull Sceptre 23 foot this fall. The boat was repowered in 1995 with twin Volvo 3.0L engines with volvo penta cobra outdrives. The boat, before I bought it took some water in the engine compartment> The seller told me it was bc of bad bellows. After assessing the transom it seems there is a 1.5 inch hole in the transom that may be the cause of this. I am anxious to get working but want to make sure I do it the right way, even if it takes longer and is more expensive. Want to sure up the transom. I am gonna take of pic of problem area and post again. Any suggestions please from a new seacraft owner