Miata won’t go in to gear / clutch not working = Clutch Slave and Clutch Master Cylinder. 

If your Miata not shifting gears / not going in to gear, this video will probably help.
Many people assume that their clutch needs to be replaced and end up paying well over $1,000 for a clutch job that they probably didn’t need yet. In the end it was likely either the clutch slave cylinder and/or clutch master cylinder.
This is a job that you can do yourself with a few tools and a bit of mechanical skill.
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Due to factors beyond the control of MiataMan, I cannot guarantee against improper use or unauthorized modifications of this information. MiataMan assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Use this information at your own risk. MiataMan recommends safe practices when working on vehicles and or with tools seen or implied in this video. Due to factors beyond the control of MiataMan, no information contained in this video shall create any expressed or implied warranty or guarantee of any particular result. Any injury, damage, or loss that may result from improper use of these tools, equipment, or from the information contained in this video is the sole responsibility of the user and not MiataMan.