We also own a short bed Lance Camper and have had one since 2001. I prefer loading it by myself, with no distractions. I just take my time and get out a few times, as I'm backing under the camper, to see how it's lined up (aligning the truck & camper got more difficult when we moved from an extended cab to a crew cab, because it's virtually impossible to see down into the bed). By doing these quick checks, you can make minor adjustments as you go.
One item that I love, and helps as you close those final few inches of space between the camper and the cab, is the foam boot at the pass-thru window. Once the gap is down to about 6 or 8 inches, I put the boot in place and back the rest of the way (slowly) until the boot is compressed. Then, as the camper is lowered, it compresses the boot just a tad more and creates a nice seal between the truck and camper. We've used the foam boots on both our Lance Campers, and really enjoy the accessory. On the road, you can have the camper and truck pass-thru windows open, or closed. On several occassions, having the windows open paid-off, because we heard something shift, or blow around, inside the camper, and that reminded us we left something unsecured.
As with all things, the more you practice, the better you'll get. Just take your time and save the beers until after you're done.
2012 F350,6.7L Diesel,4x4,CC,SB,SRW
2013 Lance 855S