Super excited to join the community

I have just picked up a MK3 TRANSIT 1992 2.5l D , as far as I can tell its has a factory conversion done by Auto sleepers but yet to be 100% sure.
Would there be a handbook or a similar file to help me understand the systems , operations and how to services ects ?
there is a million switches and hardly know what any of them does however very eager to learn.
any guidance is much appreciated .
with thanks
Yaman
some pictures attached here for reference