I had the 175cc version (Campera) back in the late 60's and loved it. The Matador was dominant in many of the eastern enduroes until the Japanese started to get serious about dirt bikes.
Wonerful torquey motor, great suspension for the day, and the engine can be modified for crazy power if you're willing to lose the low-end grunt. Main downsides are a very feeble headlight and lovely but fragile aluminum fenders that dented if a mosquito landed on them. Having to run pre-mix is also a downer for street use.
I'd keep the plastic fenders unless you're doing a restoration rather than a rider, and keep the engine stock unless you enjoy keeping the throttle pinned all the time. My Campera was like a trials engine in an enduro frame and suited my riding perfectly at the time.