I downloaded this from Resto Rick's site several years ago, since I always had trouble with proper hood adjustments;
Challenger hood adjustments
Before removing the hood hinges, it can be helpful to make alignment references with masking tape on the hood and fenders.
Also note the alignments to the fenders so you know what you have. With the fenders incorrectly aligned, the hood to fender gaps will not be parallel.
With a helper or 2, unbolt the hood from the hood hinges and remove.
Then remove the hinges from the inner fender.
For reinstalling, bolt the hood hinges to the inner fender at about midway in the vertical
Adjustment slots. Install the hood to the hinges.
Front to rear adjustments are on the hood side area of the hinges.
Up & down adjustments are on the inner fender area of the hinges.
Side to side movement is controlled by the latch positioning and fender side bumpers.
On rare occasions the side position has to "tweaked" by a push on the rear of the hood to the side, causing slight bending of the hinge arms.
The front height is controlled by the bump stop studs with the rubber caps.
A common alignment problem on E-body & 71-up B-bodies is the rear edge being up too high with the hinges being adjusted all the way down on the inner fender.
This is an adjustment problem! Start by moving the hinge up on the inner fender. (yes, up!)
Then, loosen the 2 rear bolts and leave the front bolt snug. Now lift the hood to make the hinge rotate (as viewed from the side). Retighten the rear bolts and check the fit. This procedure will get that tail to come down. Adjust the front-to-rear dimension on the hood side bolts.
It can be frustrating and take some time, but these hoods will fit correctly! I’ve installed them with the hood sitting about 2 1/2" above the fender! Within a few minutes it was fitting perfect!