Hi! i have a 1967...18 foot..StarCraft Holiday...i just replaced the transom using (2) 3/4" marine plywood..plus i used a 3/4" motor pad..plus i encased the inside of the transon,,( motor well )..with 1/8" alumium plate...my marine mechanic now tells me that the transom wood thickness is suppose to be 2 inches thick...should i redo the transom over again...i want to put a Yam F90 on my boat...is my transon strong enough as it stands now...??????