s13 front spacer question

[DriftinFrEaK69]

Hi, I was looking into suggestions for what size front spacer to use on my 4 lug front hubs. I will be putting on 17x7.5 +22 wheels with a 215/40/17 tire. I have Z brakes so im pretty sure it wont clear (wheels are still on order so dont have a clue at the time) and I want them to be pretty flush. Id like to use a small spacer so i dont have to use extended studs or buy wheel adapters.

Question 1: What is the largest spacer I can use while still running the stock wheel studs?

Question 2: What would mm spacer/adaptor would make the wheels fit the flushest?

Thanks for any help all!!