My idler wheel is dead. Is it possible to change the bearing or do I need to find a new idler wheel?

Yes Don it's for the hardtop. I've continued with the engine and front end.When it was manufactured, i bet it was done in at least 2 parts - the wheel and the bearing. Then they were pressed together. So, it ought to be able to separate and replace the bearing.
Is this for one of your factory air DartChargers?
Sweet!I think I have one for the Dart; I’ll dig it out
I'll take it Don!I’ve included pics of the wheel front and back which is identical to the one installed on my bracket. Both rotate nice and smooth
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View attachment 1716486353