79 KTM 250

[fzrr750]

Ok, guys. Here is one for you. My KTM frame vin. numbers says it is a 79. The motor ser. number says it is a 250. I have an aluminum swingarm. It has Fox Piggybacks on it ( original owner installed?). I bought it from the second owner. He said Fox shocks were on there when he bought back in 83. It has an Acerbis plastic gas tank, M. Roberts rear fender (built in number plates) and a Preston Petty front fender and small side panels (no number plates). It has no side stand (ever). How can I find out what model it is? Is it the MC or MX?
 Thanks guys for your help.   Ed T.