hi faiz ur rehman
this is new procedure or what because i heard it shall be through MOL( ministry of labor)
After credentialing your document get a letter from your sponsor mentioning of changing your profession / occupation from foreman to engineer. Download the form for changing occupation and name from MOI and filled it in Arabic language and stamped from your sponsor .take all your documents to Gharafa Immigration 2nd floor the counter for changing name and occupation. They will collect your document and will give you time to follow up the issue.
WHAT YOU NEED TO DO IS FIRSTLY GO AND AT-TESTATE ALL YOUR CREDENTIAL AND TALK TO YOUR SPONSOR THAT YOU WANTED TO CONVERT YOUR VISA FROM FOREMAN TO ENGINEER