I am not sure this is the correct map, but this is a wartime map of Northern Tunisia that contains co-ordinates J-9182.
http://legacy.lib.utexas.edu/maps/am...o-farina-7.jpg
The "J square" is on the left side of the map (right side is K). J-9182 is toward the bottom center of the map.
The map is part of a series shown here (there is an Index Map at the top of the link).
http://legacy.lib.utexas.edu/maps/ams/tunisia_50k/
The grid system being used is the "British North West Africa Grid". Another site that has these maps online is:
https://ufdc.ufl.edu/AA00001524/00001
Here is a description of the 22 April attack:
http://57thbombwing.com/321stHistory/321_BG_1943-04.pdf
Second Mission of 22 April 1943
1. Target: Landing Ground at J-9182.
2. Assault: Attack was made from East to West at an altitude of 8000 feet. The
bombing run lasted 30 seconds at a speed of 230 mph indicated. Breakaway
was to the left in a slight dive which began evasive action.
3. Own Aircraft Losses: None.
4. Remarks: Runway and L/G were hit. Flak positions on NW side of target were hit.
RR cut between AIN RHELAL and SIDI ATHMAN.
Five thousand German and five thousand Italian leaflets dropped in
target area.
Twelve 100# demolition bombs were returned when bomb-bay doors
failed to open because of flak damage.
I believe the mentioned Ain Rhelal is Ain Ghelal here:
https://www.google.com/maps/place/Ai...851!4d9.832953
and Sidi Athman is Sidi Othman here:
https://www.google.com/maps/place/Si...41!4d9.9213641
Zana appears on the map which can be also be found on Google Maps. My best guess as to the location of the landing ground would be north west of Zana, about here:
37°03'55.3"N 10°00'21.1"E
https://www.google.com/maps/place/37...1!4d10.0058611