For those of you still looking for the best way to secure your ride in your trailer. Does not come loose even on a 14 hour trip. Trailer feels more stable going down the road.
Go to etrailer.com. Look for the picture with the blue straps and yellow plates. They say that 2 wheels is enough but when all 4 wheels can be done for about $70 we use 4. Oh, plus about $20 worth of bolts from Lowes to mount the plates.
I ordered mine from etrailer.com because they were the only ones that had them in stock at the time. The price seemed pretty consistant everywhere I looked and etrailers service was excellent. Of course tie downs and trailer accessories are their business.