Tucking factory 74 bumpers
The issue with the front is the frame rails.
The production for model year '74 started out with shock mounted bumpers. Then around December, there was an issue with production on the shock mounted bumpers/brackets. So mid to late '74 got standard bumpers again. But here’s the thing, the early ‘74 model year cars only have the mount in the frame rail for the shock mounted bumper, and the shock mounts only have a single bolt and it’s in a different spot. You can see that here, a standard bumper frame rail has two mounting locations, the early ‘74 and then the ‘75/76 rails only have one (the label doesn’t account for mid to late ‘74)
Then there were the mid-to-late ‘74 frame rails, they had all 3 mounting locations to cover both the shock mounted and standard mounted bumpers. This is my '74 Duster, which had a June build date, and has both the standard AND the shock mount bracket locations from the factory. It had a non-shock mounted bumper too, which is pretty obvious looking at the wear marks on the frame rail.
So, if you have a ‘74 that has shock mounted bumpers and you want to tuck them in you can collapse the shock mounts, which will tuck the bumper in some but leave the big gnarly ends hanging out past the car.
If you have a ‘74 with standard brackets, you could either use @George Jets suggestion, or, you could just get a ‘73 front bumper and brackets. The ‘73 bumper and brackets are both different than the ‘74 versions, so get them together because you can’t use a ‘73 bumper with ‘74 brackets or vice versa.
The issue with the front is the frame rails.
The production for model year '74 started out with shock mounted bumpers. Then around December, there was an issue with production on the shock mounted bumpers/brackets. So mid to late '74 got standard bumpers again. But here’s the thing, the early ‘74 model year cars only have the mount in the frame rail for the shock mounted bumper, and the shock mounts only have a single bolt and it’s in a different spot. You can see that here, a standard bumper frame rail has two mounting locations, the early ‘74 and then the ‘75/76 rails only have one (the label doesn’t account for mid to late ‘74)
Then there were the mid-to-late ‘74 frame rails, they had all 3 mounting locations to cover both the shock mounted and standard mounted bumpers. This is my '74 Duster, which had a June build date, and has both the standard AND the shock mount bracket locations from the factory. It had a non-shock mounted bumper too, which is pretty obvious looking at the wear marks on the frame rail.
So, if you have a ‘74 that has shock mounted bumpers and you want to tuck them in you can collapse the shock mounts, which will tuck the bumper in some but leave the big gnarly ends hanging out past the car.
If you have a ‘74 with standard brackets, you could either use @George Jets suggestion, or, you could just get a ‘73 front bumper and brackets. The ‘73 bumper and brackets are both different than the ‘74 versions, so get them together because you can’t use a ‘73 bumper with ‘74 brackets or vice versa.