The 70-71 Ebody Cudas had an access hole in the passenger side rear frame for the gas tank hoses to pass through for the trunk mounted vapor tube. On my 72 I do not see a hole. Is there a "punch out" in that area, or is it a solid frame? My entire under body is undercoated and would rather not scrape away to look.

The Mopar solution for emissions regulations in the 1970s were wierd, thats for sure. My 73 Challenger had no such hole, but my friends 71 does. Not to worry. I believe they phased out the trunk tube system about the time they implemented the charcoal cannister/vacuum hose deal.

The fuel vapor seperator was moved from the passenger trunk area to the axle kick-up area just forward of the fuel tank so the hoses no longer needed to pass through the frame.. The holes weren't punched on 72 & up...

Quote "I believe they phased out the trunk tube system about the time they implemented the charcoal cannister/vacuum hose deal."

Not entirely correct the Fuel vapor seporator is still used, just redesigned... The charcoal cannister actually replaced the Engine Crankcase as the location to store fuel vapors...

YOU ARE CORRECT SIR ! I forgot about the oddball little box above the axle.