Kodiak shock

Hey guys, new here and new to the ATV world. I have a 2004 Kodiak 400 for my wife to ride and she complains non stop about the rough ride. i didnt realize the solid axle would be so rough when i bought it. I tried adjusting the travel with the bottom spring keeper with no luck.

Any ideas would be appreciated. Also if someone could tell me how long the front and rear shocks are i would appreciate it.

Ive read of guys putting snowmobile shocks in and it helping a ton, but i have no idea on the length of shock i need to buy.

Sorry for the rambling
Thanks you