Welcome 72duster to the Newmar forum & irv2.
This LINK will give you info on your slides old or new.
If you read through it the info is there.
What you will do with some help is move slide out about half way than everyone will push up on slide to place wood 2x4's under slide to holdup at a angle to check out under slide .
Its a belly job and its tough with bifocals.
If you click on the Quick Tips & Mods link below you will find allot more info that may help you.
Enjoy the forums and do post often.