Geez , Im pretty sure dare are a ton of options. On is take out the back window. Sure it will be a little cold but being a 1947 Cessna, It probabley has a cielling of only 50 feet! with a top airspeed of 80 mph, a lot less than a car. Anyway, you can pretty much get it off the ground by throwing it into the air so a board rack under the fixed gear or on top of the wing will not hurt it! it will still lift off the ground, or just put the vortex generators on the wing! or afix under the fuselage! it will take off trust me.
Didn't know you flew, Family has two, a Cherokee 235, and a Beech Baron TC58 with the Vortex.
Happy Landings!
ps Im surprised you didn't strap some Burtons on the gear for winter landing, good use for them.
Said Shred