Start out with only a pound or two...

It's best to ease into boost levels starting low and work up. This way you can tune fuel and ignition slowly. You don't have the reaction time to read AFR and make a correction before it's too late if AFR is too lean and boost is high.

AFR is only one piece of the puzzle. You don't yet know how ignition will react under boost. You need to hear the onset of detonation defined as pinging or knocking while only slightly in boost so you can correct it before going balls to the wall and never see the piston explosion coming. You can't just use the throttle to control and limit it. Detonation happens under max cylinder pressures and limiting throttle isn't enabling you to reach those levels. You must start slow and work up. Preferably with fuel that is over the top in octane and quality to what is going to be ran permanently.

This is what us folks do when we are inexperienced. I don't care if someone says you need to recheck everything or do better work or only tune once. That's bullshit. I'd love to see someone tune anything once and get it right. ******* sorcery if they could. You'll be tuning this more than twice anyways, I guarantee it. Probably more than a dozen times. And that's ok! These mods are complicated and involve many many measurements, moving parts, and seals that leak, not to mention we have a constantly changing atmosphere.

Turbo doesn't care if you bypass more or less around it to make boost. It will only act (spool) differently when you set your desired final boost level. You can start out with the wastegate wide open, as you should. Get it to idle, transition to part throttle, part throttle, 1/2 power, 3/4, full throttle, then start by increasing boost with the wastegate.