You would need to punch out the old bearings (Cannondale manual states that punching out bearings damages them) and then find a way to press the new bearings. I saw a makeshift headset press once. I guess you could use such a set up. However, I would discourage this. You damage the frame and you're toast.
The cheapest way to safely remove and install the bearings is to purchase the Enduro BB30 kit. I have it and the install/removal goes without a hitch. You can buy it from Enduro directly or from Super Fly Cycles. I think you could also find it from various other sources.
CHL