chiltons manual at the library for your year vehicle.
Depends on what engine a 1972 dodge challenger has...
1,8,4,3,6,5,7,2
Bayard Dodge died in 1972.
Do one at a time so not to mess up the firing order.
1-8-4-3-6-5-7-2
http://www.vintagebus.com/wiring/index.html
2,700 1972 Demon 340 made in 1972.
75,594 chargers were built in 1972
FIREING ORDER IS 1-5-3-6-2-4 FROM FRONT TO BACK ENG. IS 123456
A/C spark plug is---R44T and the gap is 0.035
it will be printed on the wire