Pictures are disabled on the original post - page down a little and you will find them re-posted.
Much discussion here on Rhino ramps. I had purchased all the parts to replace the water pump, thermostat and oil filter housing gasket (not related to an oil change) before I realized that no automotive parts stores in my area had the low-profile ramps. So I made my own with 2x12's. They work like a champ and would support the full weight of my house for a lifetime. Problem is storage obviously, but I keep mine down in the barn. If you have the room, these can't be beat, and NO ISSUES with clearance. If you make your own, just keep at least 18" between "steps".