For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
You should figure it out by yourself. Get a donor board and do some experiments.
first of all, temperature changes exponentially, 1cm and 3 cm is a huge difference for a hot air gun, so if you see "temp" control knob on your hot air station, you can call it a "REPAIR SPEED" and use a Louisses scale, for example, max temp would be 1.3 Louis, the lowest one would be 0.01 Louis, which is equal to 1 Apple Genius(just like Resistance/ conductivity, Apple Genius is a reciprocal to Louis).
The best iron temperature varies, i prefer ts-100 with a custom firmware - i have 320°C as a normal temperature and 400°C as a boost one if i need more heat instantly.