I've added two links that should be beneficial to you to help you remove your mower deck, however, I am not sure what kind of mower you have since you did not specify. Hopefully these will help you, if not, let me know what kind of mower you have and hopefully I will be able to be of assistance!
Type in 71243 in the search. You want to click on the red tab that says "manuals". Look for the english version, if that is your preference. Click on the red text and it will open up a .pdf with your operators manual. Think it was on page 33 that gave belt lace instructions.