Not cheap for a fue injection!
A colleague is currently installing fuel injection on his VW engine sitting in a Porsche 356 replica he has built on a shortened buggy chassie.
He told me to add one on my bike after our carb jetting stories. He had some Weber jetting issues last year so he enter next level.
The system is not that expensive taking care about ignition too. Lambda sond in exhaust will report the result back to the injection control. US made stuff. Circuit board to be built in a box. Maybe 200x150x50mm in size.