Block the wheels on both sides of the trailer with wheel chocks. Use the manual tongue jack to raise the trailer. Put jack stands underneath the trailer's A-frame. Retract the tongue jack until the trailer rests on the jack stands. Try to move the trailer by hand to make sure it's supported securely and will not roll.
Unbolt the manual jack and remove it. Use a utility knife to carefully scrape away the paint around the bolt holes. This will ensure a good ground for the electric jack.
Insert the electric jack through the hole in the mounting plate. Secure it with nuts and bolts. On some models, you may need to adjust the power head to provide clearance between it and the propane tanks or truck lift-gate. Follow the manufacturer's instructions.
Connect the fuse holder/power wire from the electric jack. Connect it directly to the positive terminal of the trailer battery using crimp connectors. Use electrical tape to seal the connectors and prevent corrosion. Move the wire out of the way.
Check for proper operation. Raise and lower the jack post using the switch on the electric jack. On some models you must synchronize the post with the power head. Follow the manufacturer's instructions. Lower the jack post to support the trailer and remove the jack stands.
