Find information and documents or repair instructions for Vario 612 with OM 602

Hello Perhaps one can help me here. We have recently bought a Vario 612 Bj. 2000 and converted it to a Womo. The engine is the 2.9 liter five-cylinder with 116 Ps. Before it was a double cabin with platform and tarpaulin, now it is a single cabin with duere construction. Everything with blessing from the Dekra. My problem is the following, I am looking for documents, explosion drawings, repair instructions etc. for the Vario, only for the Vario and not for the construction. I find in the net no documents that would be helpful to me during repair and maintenance work. I would like to know where the component is and how the compressed air supported braking system works. Hold a repair instruction would be ideal. Also for all other information I would be grateful. I hope that one can help me here. Greetings from Meckpomm