drain hole configurations?

[Kracker Jack]

like Maco joe said im thinking to hard. what i kinda want to know also when the boat is on the trailer how does the sump drain from rain water? i take it there is a drain plug i need to drill in that recessed sump well? I apoligize for asking all these questions but the po had the transom set up all wrong he had the sump well draining into the bilge, and the only other v20 ive been on was my dads and it was a self bailing with a higher floor.