They will fit just right but...
-The performance will not be optimum because their jetting is for 1.5. That doesnt mean that you will have problem , the engine will work fine but with propper tuning can and will perform better.
-YOu will also have to change fuel pump as the one for injection give more psi and will flood the carbs. Either you install a fuel regulator or installing another pump with the proper pressure.
-Along with the webers you should have the complete set , linkage and intakes because injection intakes are different.