I just got a 98 HR Endeavor 37cds.
No slide locks on mine either.
My process to put the slide out has been:
Park
Bleed air bags
Level (fronts down to touching ground and take a little weight, then same with rears. Then follow lights)
Put out slide
Mine has a manual leveller and shakes the rig pretty bad when deploying them. Did not want to have the slide out while leveling. I have to get some
Jack pads and something to drive coach up onto to level front to back. Also need some wheel chocks.