...as they were put there to match up with the recycled Hemi Under Glass chassis plate. That body was reworked from the 1970 MPC Ramchargers funny car (they had a '67 Dart but their '70 car was a Challenger).
The Ramchargers Dart body has a front bumper, but the front wheel openings are too far forward as it was reworked from the 1969 Charlie Allen funny car. Best shot at a '70- '71 Dart now would be to find a Ramchargers Dart body and move the front wheel openings back a bit.
--Mark