No, you can't just add larger front rotors. That will throw off the front to rear brake bias. If you go Giro, you need both front and rear rotors at the same.
If you are getting into DEs, I would strongly suggest the brake upgrade. What is the most important part of your car when you are going 100+ mph into a 40 mph corner. Stock parts are ok, but I would put my first money into brake upgrades to stay even safer. They work better, run cooler, fade much less, last longer, and are less likely to fail or have a problem due to their higher capacity to stop the car.
Caliper bolts definitely add convenience for pad changes and also safety by reducing the wear on the aluminum upright that they bolt into. Not sure how taking out the old ones will affect that aluminum upright. I would just call Ira at Target Engineering and explain your situation. He might be able to recommend a stud length that could work for your stock calipers and one that could also work for the larger Giro Disc rotors and their spacers. The difference will be 10mm more for the Giro setup. I just ordered 85 mm studs for my PCCB calipers.
If you are getting into DEs, I would strongly suggest the brake upgrade. What is the most important part of your car when you are going 100+ mph into a 40 mph corner. Stock parts are ok, but I would put my first money into brake upgrades to stay even safer. They work better, run cooler, fade much less, last longer, and are less likely to fail or have a problem due to their higher capacity to stop the car.
Caliper bolts definitely add convenience for pad changes and also safety by reducing the wear on the aluminum upright that they bolt into. Not sure how taking out the old ones will affect that aluminum upright. I would just call Ira at Target Engineering and explain your situation. He might be able to recommend a stud length that could work for your stock calipers and one that could also work for the larger Giro Disc rotors and their spacers. The difference will be 10mm more for the Giro setup. I just ordered 85 mm studs for my PCCB calipers.