REEPER 4 x 4

I need help please. This is all new to myself & my husband. We have gotten 2 used fourwheelers so we can ride with our kids (kids have go carts). One of the 4wheelers is a 1998 Suzuki Quadrunner 500 4x4. It has rearend trouble. 
We are having a difficult time finding new or used parts, & no luck with aftermarket parts. 
Hoping someone here can help. We were told by Suzuki dealership that some Artic Cat parts will interchange, but he wasnt sure which ones & said there are companies that produce aftermarket parts, but wasn't any help there either. 
Any help or information is greatly appreciated.... Thank you.

STREET LEGAL - ONE OF A KIND HARLEY DAVIDSON 4-WHEELER $9,500 OBO Sporster 883 bored to 1200cc built into a Street Legal Licensed and Insured 4-Wheeler. It has 400ex front end, 250r Rear end. All chromed out with new black gloss paint. I have a $500 Dakota Digital Speedometer to go with it (needs installed). I also have an extra rear gear and extra set of off-road mud tires and rims. Brakes need to be adjusted, and there's a few other touch ups that will place it into show quality. I haven't started it in a while. Ran Great last run. This bike has over $20k invested in work and time. It will go about 120 mph or more. With the other gear it will go about 60 mph. It rides great on and off road. It brings trophies and turns heads at shows. Shoot me a message or offer if interested. (May entertain trades). I will entertain any offers. This is your only chance to own a Street Legal 4 wheeler. Currently titles and registered in KY.

Wiring diagram for 2007 Arctic Cat 700 EFI 4x4
 
 

i have a 1993 timberwolf yamaha and the compression is good and lights work but for some reason the electricity is not going to the spark plug(s)! i got a friend to check it out and they said its no use but im not giving up! please help with this!