Mac,my '95 service manual says 1340 ohms with transmission warm. There is also a chart that has resistances at different AT temps,35,990@ 32°F;1340@80°;410@120°. It seems to me by looking at these values that a resister of 1340-410 ohms will work,make it a 1k and it's easily available. If you are concerned about shifting into high gear when the engine is cold you can just push the OD off switch for the first couple of miles.
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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)