After the scripted Buggy race and after completing Sub Story 24 – Yosumi’s Seeds. Head back to the Highland Village and you should see an old man by the Well.
After speaking to him you will then be tasked to hunt down some materials, you will need the following; x4 Fine Cogwheels, x3 Fine Nails and x3 Plastics.
If you do not currently possess these items then they can easily be found around the Wasteland and near the Highland Village just keep driving into items and you should end up with enough.
Return to the old man and hand him the items and after that leave the Village. Once again return to the Village and talk to him once again to end the quest!
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