there were no factory one ton 4x4's until 76 or 77. there are, however, some Napco 4x4 conversions of factory 2wd 1 ton trucks of this era. they are rare, and use a modified Eaton rear axle up front that has drum brakes.
your plan sounds good. I also bought a dodge dana 60 front axle for $150 and it will be going under my truck some day.
