I know of some people that have done this but it’s not a good option in my opinion. Having two separate ecu’s controlling things with no communication between them and little understanding of how the oem ecu controls things is bringing a lot of risk to the party. For instance if the oem ecu cuts fuel as a limiter but your port injectors are still squirting you are probably going to melt parts quickly. With port/DI combos there are many other scenarios where the timing difference between the two injection events can cause very lean cycles also.
Fair enough if it’s a junk yard engine with not much value and you are prepared to learn by breaking things...
