Hi, and welcome to the forum!
There are currently no soldering instructions on the wiki. We would love to create a comprehensive self building manual, but at the moment all the resources we have are dedicated to the development of the software roadmap and creation of a new user documentation.
You can find several threads about soldering and building in general here in the forum. For example:
If you need further information we are always around to give advice and guide you if needed. You can also ask some of the users who had went through the building process or have soldering experience such as @highmatergogo, @valor, @Dodo2207, @ComradeZoned.
Keep in mind that the current official version of the KCeptor is the R2.3. There's also a nice alternative created by @valor, you can find it here: https://forum.chordata.cc/d/71-mini-k-ceptor-design/13
It would be great if we can start putting together a community contributed self building guide. If you are planning to start building the hardware yourselves please consider documenting the steps in a didactic manner so we can use that material to create the guide. Or even better, can also directly contribute to the wiki 😉
PS: please fill the user profile section on your accounts, it will help us and other users understand your background and give better advices. Info on how to do it here