I would suggest getting a dedicated 14-50 plug for your car if you can.

Do you already have the amp requirement (50amp breaker) on the 6-50 plug? if you do, unless you use if for your dryer or something similar, just change the plug! get this https://www.amazon.com/gp/product/B00IPBMUKY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 and someone to install it