New Axles Belly Pan Removal?

So I've seen axle replacement done in pics, but now that I have my new axles ordered, I went under to spray the bolts with pb blaster. Unless I'm not getting it, it appears I have to remove the pan covering the tanks, to get at the axle nuts. Yes the heads of the bolts on the outside of the frame rail are accessible, but I don't see a way to get, forget about a socket, or even a box wrench on the inside nut. The threaded end of the bolts are probably less than a half inch away from the side of the pan, and most of the axle replacements I've seen, are hanging below the tanks. Am I missing something here? 1990 29 excella