bumper swap

I recently got a 06 ranger that had front end damage and ive gotten the header panel, headlights and corner lights from a 04 on the front now. When I go to put the metal 04 bumper on, it lines up good until I tighten the nuts(the 4 18mm nuts holding it on) then it just tilts down on each side...

alright Im new well I posted once I got my 98reg cab 6ft bed 4 banger ranger im looking to put a djm lowering kit 4/5 plus c notch on it which I have sitting in boxes in my garage and looking to put on the 02 chrome top edge bumper with fogs which I just seen on this site wondering what the...