I know you said you wanted to DIY but for the hassle of finding a place, the task itself, wrench, drain pan, buying the oil and filter and disposal of the old oil I would just take to a truck center or RV dealer to have it done. Anymore you don't really save a lot of money doing it yourself and it's certainly less hassle and mess. There is a reason CG's don't want people changing oil and primarily it's the risk of a spill and the disposal of the old oil. I think you'll find the same concern anywhere you would try and change it that wasn't personal property.