You might find something of value to your project on one of those websites.
I guess the biggest question for yourself is: How much work do I want to do? If you are willing to do 100% of the work yourself, go for it! The final product is very rewarding and it can be done for a fraction of the cost. However, there is a B-I-G difference between wanting to work on a motor, and having to work on a motor.
I wanted to add Whipples to my motors, and I had a fun time doing it. On the flip side, I needed to flush all the mud out of my motors this past Friday and I hated every minute of it. The more you customize your project, the more difficult time you will have finding somebody to work on the project for you. Again, if you are willing to go balls out and do 100% of everything yourself... then this is not a problem. But we've had those days where the last thing we wanted to was wrench away under a hot engine hatch while everyone else is enjoying their mild / stock powered machines!
yes the boat is a 23'powerplay I don't mind building a motor myself wouldn't be the first but never in a boat. Wasn't sure if anyone tried a stroker motor in a boat - if the bearings lasted (crank and rod) under the rpm and stress