[JPK]

You are not looking at the correct documentation
If you accessed to the documentation through the site Support/Technical documents menu, you may not be looking in the right place. The kits evolve in time, and we keep every versions of their documentation.
Only take your documentation at the url address marked on your kit box, something like https://www.soundskulptor.com/docs-xx.html.

Component soldered in the wrong place
Do not try to save the component! This will very likely damage the PCB which cost 100 times more than most components.
Except for transformers which are also expensive, cut the components pins with cutting pliers in order to be able to remove the pins one by one.
Then empty the holes with a de-soldering pump (this one works great : Jonard Industries DP-100).

Untrimmed component leads
Check that no component lead is able to touch the chassis plate, the test pins in particular.

Soldering too fast
When making a solder joint, beginners are often afraid of heating too much the components resulting in a lot of dry joints. It is necessary to put enough heat on the component pins so that the solder can flow into the hole. 2-3 seconds heating with an iron set to 300-320°C (507-610°F) is not a problem for most components.
The only components that may suffer from to much heating are the pin headers when the plastic part that holds the pins together start melting, messing the pins position. For these, you can press the component on a wet sponge while soldering.