Nate, do not even think twice about tapping the oil pan. It is simple to do. I've had 3 blowers on my last vette. A
Vortech V3 SI, a Vortech V7 YSI, and a Novi 1500. Vortech owns Paxton, same blowers in similar sizes. For instance, an SI equals a 1200, a T-trim equals a 1500, a JT trim equals a 2200. And then it ends there. The YSI is smaller than the Novi 2500.
My car made around 700rwhp on the stock motor at 10psi with the SI trim. 850rwhp with the Novi 1500 at 12-13psi on my 402. Didn't ever get the YSI dialed in(belt issues), or install my Novi 2200, but I'm sure both would have made in the 900-1000rwhp area, so that just shows you all these blowers are very capable.
You will build up the IAT's a little more with a self contained unit, but not a big deal. Change the oil on the first break in at 2000-3000 miles, then every 5000 miles after that if you go with a self contained unit.
The single best thing you can do for any centri kit is buy a meth kit. They are very simple to use, and you can run 1000 miles without using a drop of it if need be. Your tuner can program it to come on at a certain boost or RPM level when you go WOT. This will dramatically decrease your IAT's, add power and safety. Your tuner can tune in to it to add power with the increased octane by bumping the timing up, or tune it just for safety so if it does fail, it's like a normal blower tune. There are a lot of ways to set up meth, and your tuner, if experienced, will know best. I honestly will never, ever install a blower on any car I own without meth.
As far as the cam selection, I'm not sure. I've looked at the 2v cam specs, and have run them in one of my 2v's before. Some will bleed off boost a little more, but most NA cams work great for centri cars since the power curve is similar to an NA car, just higher, while turbo and PD cars hit much harder down low.
Honestly, I wouldn't even consider a big difference in tapping the pan if you find a good deal on a V2. It is simple, doesn't look ugly, etc. Both the V2 and V3 SI trims are 1150CFM blowers and will make the same power.