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I have a topographic survey on autocad (.dwg), and I need to model the terrain precisely on sketchup. I've tried a lot of things, but it's either very time-consuming or ineffective with Sketchup's tools. Could you help me? I am attaching the file to you.
Use Selection Toys to isolate items you need to remove...
https://community.sketchucation.com/post/1052264
Your points are components instances so you could use Instances > Select All to select all the guide point instances. Then Group that selection and enter the group. Explode the point instances to realise them into the model space.
Exit group and use Toposhaper.