I have a 2902SS and my slide fuses are under the trailer tongue, back behind the propane tanks. On mine, there's an in-line 30A fuse for each slide.
When I picked my camper up new and took it on its maiden voyage, neither slide worked... Turns out both fuses blew. On my camper, if I don't bump the switch when the slide motor gets under pressure, it will blow the fuse. I'm sure it's not right, but I can live and adapt to it...
On mine - Looking from the front of the camper to the back, the fuses are on the right hand side just under the front of the camper.