Daytonas definitely have an external fuel pump, same as pre-2003 V11s. Not sure about the Daytona fuel tank fitting your V11- I am sure it is possible but you may end up changing other parts like the seat unit to help make it fit.
Would probably be easier and cheaper to slot in a complete Daytona / Centauro engine in place of your V11 motor, rather than try and work out what you need to do to mate the 4 valve top end onto your V11 crankcase. You could then sell your V11 engine to part fund this.
I know a few others on this forum have done exactly this and can probably advise how it is done.
Cheers
Guy