You'll never get to Stage 4 (no longer an Aspie), because it's medically impossible.
The closest you'll ever get, with lots of help from amphetamines or methylphenidate, is a point where doing the "normal" thing becomes a semi-automatic reflex. But don't kid yourself. You'll *never* get to a point where you aren't aware that it's all an act, and that you're just biting your tongue or doing certain things because the consequences of NOT doing so are public scorn & ridicule.
Furthermore, as others have noted, this stage is rarely sustainable. Pulling it off successfully is a *huge* amount of work, and few have the stamina to keep up the act forever. The usual next step is either withdrawal (downtime to recharge & heal), burnout (throwing in the towel & giving up the act), or possibly despair & depression.
Personally, I settle for comfortable healing solitude, semi-weirdness at work (easy to get away with b/c most of my coworkers are similar), and working hard to be "99.9%" 'on point' when I go out & have to be social. I have no illusions about the strategy being viable if I got into a real relationship (I can't be on stage 24/7 without burning out & cracking in a matter of days), but that problem usually solves itself anyway. If somebody insists on latching on to me, I just drop the act until they leave me alone & I can go back to having a happy weekend social life in manageable, bite-sized doses.
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Your Aspie score: 170 of 200 · Your neurotypical (non-autistic) score: 34 of 200 · You are very likely an Aspie [ AQ=41, EQ=11, SQ=45, SQ-R=77; FQ=38 ]