You are likely overthinking this and likely your measurement is sending you down the wrong path. You can not effectively troubleshoot using resistance measurements, most of the time, because of bad connections, which come and go.
I use a "mix" of tools. One is an old tail/ stop lamp with pigtails. This is useful for a lot of stuff. When using it as a test lamp, it LOADS the circuit, so that if the circuit has bad connections, it will not light, unlike your meter which draws a tiny amount of current, and which often flows through the bad connection with no load
The circuit for the signals is quite easy The "functional path" is:
From the switched fusebox buss and fuse, to the flasher, and from the flasher to the turn signal switch. The switch connects the various circuits and feeds flasher power out to whichever lamps is selected. There is one connector for the front lamps right at the column, and then through the bulkhead, connector, and then to the front lamps.
THE DASH INDICATOR lamps "Y" off from the column connector, so if you have power there and the dash lamp works, it is the circuit between the bulkhead connector and the socket that is bad.
GROUNDS can really screw you up. Some sockets have a separate pigtail ground and if mounted in the grille, GET A POOR GROUND. Sometimes you should solder a grounding pigtail right to the lamp socket and run that to the body Obviously, rust/ corrosion in the socket or lamp itself is an issue
THE SOCKET PIGTAIL. These can screw with you because the "key" can wear or break, or if it's been replaced, may not be correct to hold the pigtail in alignment. In other words, the contacts are not aligned to the lamp, or are in such position to cross connect
LAMPS Lamps can have weird intermittent and act almost like a flasher, with the filamanet making and breaking. IF THE GROUND to the shell right in the lamp is broken or "iffy" this can drive you nuts. Always have/ try more than one bulb!! The filaments can "cross connect" internally, EG when you turn on the tail lights, one side will light brighter because the filaments are interconnected. When you operate the signal, both sides will flash
This is all simple stuff but can screw with your mind.
Last you can download an aftermarket diagram from MyMopar. These are not as detailed as the factory diagrams. You can also download SOME YEARS of the factory manual there, all free. Some of the manuals there came from the guys right here
