Back side down. I have an Viair that will bring it up to running pressure if need be. I had a blowout about an hour out of town and the service sent by Good Sam had a H of a time getting the nuts off. I suspect that the RV service center that did the bearing repack put the lugs back on at about 400 lbs.
Just a lesson here. I Have been dealing with Discount Tire for 40 years plus and several times they have reminded me that I should only run RV tires three years. Really, really top grade tires you might get four but in Arizona, even though I store fully inside, 3 years max. I went close to four and with all honestly, about 5 minutes before a tire blew I said to my wife, "this is probably the last trip on these tires since they are approaching four years". Yep it was the last trip on them alright. From the tire change location we went right straight to Flagstaff Discount for five new tires.