Good site to check is FMCA towing guide
This is for 2004 model year: http://www.lichtsinn.com/pdfs/dinghy-guide-2004.pdf
2WD Ranger with MANUAL transmission is OK to tow with 4 wheels down.
Automatic is NOT, pretty much no 2WD automatic is towable with 4 wheels down
Some 4WDs with automatics can have a Neutral selection added to the electric shift transfer case, these can also be "flat towed", because transfer case is in neutral so transmission isn't connected to rear wheels
In the RV world "Dinghy towing" means towing a vehicle with 4 wheels on the ground.
You need to leave a key in it and turned to first "click" so steering wheel is unlocked
Make SURE parking brake is released, I know it sound like a DUH, but you would be surprised at how many people forget and with a bigger RV you won't feel it, but may see the smoke after a few miles, lol.