Modification of preliminary decree in partition suit

In a partition suit, preliminary decree was passed in 2010. Final decree is not passed. Final decree proceedings are in progress. Now, I want to file a petition to submit additional evidence (revenue records, patta etc) and pray for modification of preliminary decree. Under which order, rule and section of CPC should the petition be filed? Please advise in detail. Thanking you, Y. Vijay Kumar, Hyderabad, Telangana