There is always something on FleaBay for this. I have a CB300 manual around for the Dodge but yours may predate the one I have by a bit. My Tioga was a '77 on a Dodge van.
I've got a brand new Haynes manual for the 1971-2003 (wow!) Dodge and Plymouth Vans. You can have it for shipping, figure 5 bucks. drop me your address on a message and I'll send her off to you! I had 2 from the '77 Tioga. One is still in the RV the other was at home.