If you are bracing off of the front of the intake, where the majority of force is, it is best to transfer punch the mounting holes directly as you might find that they vary slightly. Use the two outside bolts because the two center bolts are already pretty long. Just in case ours are the same, the outside bolt holes are 9.313 center to center. From port to starboard, the center to center actual measurements are:
2.993, 3.321, 2.980 for the bolt holes across the front of the intake
2.905, 2.949, 2.885 for the bolt holes across the front of the suction housing
Be advised that they are usually not drilled straight inline. These have very sloppy tolerances.
Let me know if you need anything else.
Cheers,
Joe