How to use item.php in my own theme folder?

I have create a Product type and I copied a Flexicontent template to use for it.  It duplicated the grid folder in the com_flexicontent/templates folder. It also copied ALL the files, and I really dont need anything other than item.php because all my styling should be in my own theme. I am making a custom theme, and so not want any unnessary code or styling. So I reduced my new product template to only item.php and only outputting my own HTML and code. So thats working well. 

BUT I do not want to have this in the com_flexicontent directory. I want it in my theme folder. 

So how can I load my own theme template file for this product page? I suppose I could use an includes in the com_flexicontent item.php but it shouldn't really be necessary. 

Even if I can just use my themes index.php file and check "if type == product" then include my product file otherwise load index. Is this possible? 

I try to keep things simple in my themes, only using code I add and no need for anything else to interfere. 

Thanks a lot

Laurence

Also, I just noticed this in the console:
index.php:1 Refused to apply style from ' mydomain.comk/components/com_flexiconten...product/css/item.css ' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.

So I assume Flexicontent is trying to load a non-existant css file even though I do not call it in my item.php?

So I am definitely going to need to know how to override this flexicontent template as I dont need or want any references to unused things. Thats one reason I am trying to create the template myself.

Let me know if Flexicontent is the wrong extension for just adding custom types and fields.

Thanks!

hello you can't (or its not recommanded) to try change specific flexicontent template system ... to many relation (frameworks, css override etc) will be broken
it like to move template file of joomla ... no sens
about css you can create you own flexicontent.css in your templates/your_template_css/
for item.php code i recommand to use item_html5.php file => more cleaner code