Too many engine choices!

If you EVER decide you don't want that SU setup, give me a call! But my vote would be for DCOEs, or custom fab a manifold to use 6 Kehin motorcycle carbs.

BTW, the left SU needs it's dome rotated. Those look like HIF6's, probably from an early 70's Volvo, or Hitatchi made carbs from a 240Z (2 fronts and a rear).