We got a Burley trailer at my wife's baby shower (isn't it nice when one of her uncles is a hardcore cyclist?) and I'm ready to hitch it to my bike to do some short errands, and in another couple of months, put my son in it! In anticipation, I assembled the trailer and realized that my K2 Razorback mountain bike (I'd rather use the bike with SPD pedals for walkability instead of my roadie with duck shoes) has recessed dropouts. They're kind of like Breezer dropouts, but not nearly as deep... maybe 1.5-2mm. Anybody know if I can just put a washer in between the dropout and the trailer hitch? I can't use a classic hitch because it's a full suspension bike with pivots in that area. Thanks in advance.