Turn-Key Crate motor success stories?

Can anyone tell me about success they have had with engine builders with Turn-key crate motors in their mustangs? Specifically 351W's. I am looking to replace my existing 351W in my 69 convertible. Looking at getting between 350-400hp. Also, costs of the motor. Any other info would be greatly appreciated. Thanks and happy new year.

Working my original block is something I am also kicking around. I have a local speed shop who I will speak with about that. From my research a good possible solution may be the Edelbrock 351w "Power Package" which they say will create up to 400hp. If a rebuild,parts (edelbrock Power package),labor comes close to the cost of a turn-key (and when I say close I am talking 1-2 grand, I'll keep my stock motor on an engine stand in my garage looking pretty all cleaned up and keep it stock in case I want to convert things back to stock some day and put the crate motor in it.

Also, thanks for the offer of the motor; however, at this time I would choose to either build my stock 351 or go the crate route. Thanks again.

Thanks for the advice. I have added it to my list of possibilities. There are so many options. Even the research is fun. Thanks again.