Slide out problem . . . help please

[KLBuhr]

Guidance needed . . . our 2003 MS RV sat for the better part of 3 years. Now, I am having trouble moving the slides out. I crawled under and see there is a way to move the door slide out (?), but there is limited space to get in there and try to move the slide out. (Our RV is parked in a friend's farm lot, away from a RV shop.) Is there a way to move the slide manually?

[fjr vfr]

First, I have no idea what a 2003 MS is? My advise is go to You Tube and search your brand and model trailer slide problems. Someone will have a video.