I too recently bought a Micargi and a 66cc motor. It's for my second build. I haven't been to the house for a couple months and haven't seen either kit or bike yet
I bought the Micargi Pantera 7 speed, blue. I think both frames (yours and mine) have a larger front pipe. My kit comes with "Universal Plate U Bracket for Larger Frame Tubes". I think the angle of the front pipe is different from my first build. I've read how some have used u-bolts and sheet metal or metal straps like some muffler straps to make the front attachment. I'll bet some vendors also have some nice mountings. My first build was on a mountain bike with a strait pipe and fit together with my kit as though they were built for each other. Hopefully your kit came with the universal mount and it works. I sure would like to see pictures of your build and mount. I'd at least like to hear how you resolved the mounting issue.