A 3 page document needs to be paraphrased completely to eliminate plagiarism. the word count should not go down by any number of words although it can be increased if required.
Technical terms would for sure remain the same but it is important to change the sentences to avoid being plagiarised.
Hello, I am an experienced translator and proofreader. I have receive a BA degree in economics (studies in English), therefore I can assure I do have an extensive vocabulary for this task. Thank you for your consideration, Darja