I hear you, they should have made an access panel from inside the cab. In the end, that is what I did. I cut a fair size chunk out of the firewall/tunnel on the passenger side. It gave me great access to the CPS. A bit of tin work and I have an access panel. This is my snowplow truck so, I am not too worried about the little damage I did.

 

One final update. My 1997 Ram 2500 5.9L Gas after working great when I last used it. It is only used for snowplowing my long country driveway. One day, after sitting for 2 weeks, I started it and it died after a few minutes and wouldn't start. My first thought was a frozen fuel line. I put Isopropyl Alcohol gas anti-freeze in the tank and waited a day. Next day it started and ran great for a couple minutes then died and wouldn't start. My brother has a 96 RAM 1500 and he had to replace the fuel pump, so I replaced the fuel pump. Not the problem. I then noticed when it dies it was like the ignition was just shut down. A friend suggested cleaning the Throttle body. A search on this forum also indicated the Idle Air Control (IAC) could be the problem. Made sense, since it died about the time the choke should open. Replace IAC, ran for 1/2 hour. Thought it was fixed...wrong. Started doing the same thing. It died at the end of the driveway. Next day it started up and I was able to drive it to the garage. Replaced the Throttle Position Sensor, didn't fix it. (I can now pull my TB off clean it and and reinstall it in about 5 minutes.) Codes to this point had been P0340 and P1391. Now Also P0320. This forum also indicated the Crankshaft Position Sensor (CPS CKPS). Many people said possibly but normally is won't start at all. It started and ran great for 5 minutes when cold. I went to Dodge and paid $94 for a new IAC. Put it in and the truck ran great warming up fully, and restarting. I was re-hooking up the plow, truck idling nicely, it sputtered, died, and wouldn't start. I decided I would change the CPS, but the task is nearly impossible for me. With short fat arms I can't get around the Catalytic converter from underneath. The engine is so far back under the firewall, my short fat arms and old body could not contort enough to get it from above either. I cut a hole right of the air bag and below the heater on the firewall/tunnel. If you do this be careful of the seam and the heat shield. after you pull the carpet down and remove the rubber and foam insulation you can see a bolt that holds the heat shield. Just stay left of that. Took about fifteen minutes to change the the CPS by myself with my new access point. I had extra tin, so no worry about the extra access point. Dodge should have made it part of their design anyway. Would love to talk to the engineers about engineering for maintenance. The CPS was the problem. Truck runs great with no problem. Note that if you have a code reader, the code P0320 would come up instantly when the truck ran after clearing the codes. Again and again it did that. After changing the CPS, no codes. Even after running for 1 1/2 hours clearing the driveway of snow.
I hope this helps someone not get a frustrated as I did.

 

Man glad to hear you got it solved. Never surrender.