zbrush to blender question

Hey all. So I’ve successfully brought model and texture into blender from zbrush. It is very high detailed and many polys.

I know I can bring the poly count down in zbrush but when I do and export, the high detailed texture wont fit the model.

So what I want to do is in zbrush is create a higly detailed polypaint texture. Use decimation master to bring the poly count down considerably on the model. Export the high detailed texture and the low poly model so they will work together. I’ve used uvmap:puvtiles for uv coordinates. Hope this makes sense

Any suggestions the steps I must do?