what do the support brackets look like?? Can you make your own out of a grinder and drill. Perhaps drill holes in the bike and bolt your custom brackets. I wouldn't mind helping you out if you give me measurements and a picture I could make them and send them to you to scale in the mail. Is your bike steel? Then have a friend tack weld onto the frame. Point is don't let if the kit will fit or not ruin your whole project. Carry on and adapt.The brackets are adjustable i'm pretty sure but I will have to make a part list soon. Might get a street fighter type headlight red beard's garage used one on his street legal minibike build and it looks pretty good. As far as I know they make suspension forks for fat bikes. May as well throw in bigger discs for the disc brakes. The thing I'm worried about is the support bracket that goes up from the tires on the GEBE kit if it will fit or not the tires are 4 inch.
If you give me the dimensions and scale, I can make it for you. You just have to cover shipping. Probably be 30 dollars. I have a friend at a construction site who gives me scrap steel.https://www.bikeengines.com/shop/lower-mount-strap/ $60 for a piece of steel I could probably make myself. That's what I mean by the kit seems like too much money, $350 without an engine included $699 with an engine. Of course i'ts probably better steel than from mainland China but still $60 is way too much it should probably be close to $20-$30 in my opinion. There is that bracket and then one that bolts where the brake goes behind the seat area from what I've seen.