Believe it or not, the best place for the injector is outboard of the trumpet.
Makes the most power.
Injectors are typically aimed at the back of the intake valve for fuel economy and lower emissions.
Rune, you can buy "reversing plates" for IDA manifolds, and do just as you describe.
Scroll to the bottom.
http://www.compcams.com/Technical/Ca...pdf/page22.pdf