True, it will take some work.If you go with a Spica TB setup, then I would recommend that you fit a throttle position sensor. If you make an adapter, it can go on the end of the throttle shaft on the rear end of the intake assembly. The Alpha-N fueling algorithm is preferred for most individual runner applications. We tried to use the mixed TPS/MAP algorithm, but ultimately went full Alpha-N Additionally, you will need to machine the Spica injector ports so your EFI ones fit and add some mounting points to hold the fuel rail in place.
The nice thing about using an L-Jet Spider manifold is less modification, and you can use both a TPS and a MAP sensor, if you want.
The idea would be to use it on a twinspark manifold. Some fabrication would be necessary but the original manifold already has the injectors installed.
All that is really needed is the butterflies and TPS.