I have a 73 challenger and was wondering if you can change to earlier bumper brackets to move the bumpers in closer,and maybe do away with the bumper fillers etc?What year fits.Anyone done it?Pics?

I think it will be fine to make the switch with the rear bumper.I do think you'll need the earlier year rear bumper though. The 73-74 rear bumper is attached to the bracket with 3 bolts on each side. The 70-72 attach with 2 on each side. The earlier year bracket holes won't line up to your 73 bumper holes.I'm not sure about the front.
Scott

I changed mine out last year...I got '70-'72 brackets and bumper.

I did it to my 73 Challenger. For the rear, you'll need the thin metal filler from 70-72's, the two small vertical bumperettes to replace the huge 73 guards, & you'll need to remove the "V" shaped license bracket.
The front is much easier. 70-72 style brackets, rubber wedges for the bumper corners, & possibly a new license bracket.
Keep in mind that the earlier bumpers used a jack hook which lifted from under the bumper, while your jack has a tab that goes in a slot on the bumpers.

I did this myself on my 1974 Challenger using 74 brackets AND bumpers. (Check out bumpers in sig pic below) I drilled new holes through the front bumper brackets for the bracket bolts that go into framerails. I think it was 1 1/2" towards front. (There was a MOPARTS post on the front swap awhile ago) Clamp both brackets together in a couple of places so they don't move. Use a drill press. There is a square locating hole for first one, and then drill same distance for other two. You will start to get into the "curve" of the bracket when front hole is drilled, but it works fine.
For rears I just cut the brackets, overlapped them 1/2 the distance I wanted the bumpers to come in, and welded them back together all the way around. Looks great and got to throw away those huge heavy inner supports.
Only thing I have left to do is make some mounting brackets for the 70-71 bumper guards to cover the two holes in the rear gravel pan left where those fugly '74 guards used to be.

Thanks for the info.