is this a good combo for street/strip use

As long as you have the right carb for that set up you should easily get 250 rwhp. I would go with the holley, just because I have more experience with them.

if the car is going to be driven a lot on the street I would personally run the edelbrock carb (carter) I've run both holley and carter carbs and currently run a holley 650dp.

If you're deadset on running a holley for the performance gain, I would recommend getting one built, Jesse Bigs at www.bigsperformance.com built my carb and he was recommended by a bunch a guys on another forum. His carbs are awesome and he builds them according to your combo. My carb runs flawlessly. You could possibly achieve similar results without dishing out $400+ for a carb but be prepared to do some tuning.

Holley's will make more power but carters are much easier to tune, get better gas mileage, and never give you problems, no power valves to blow or leaking gaskets. Carter's are a very simple design and once set up properly will give you years of service.

Unless you already have the F303, you might consider calling up different cam companies for recommendations, the F303 is a single pattern cam 226@.050, depending on the heads there may be a better cam for your combo.

As far as the intake goes, go with a performer RPM, or Weiand Stealth, the rpm air gap is also nice but more $$.

Carb spacers will affect power but for every engine results will vary. Hood clearance may also be an issue depending on the car, but typically open spacers are good for High rpm power and the 4 hole spacers are for low end torque.