I used the 605HD with #650 oleos struts. I double backed the cross member wood mounts and doubled the the wing spars at the leading edge. I cut off the coil on the 605hd and mounted the oleos with an 1/8 inch clearance from the base of the retract. I figured the oleo strut was designed to asbsorb landings. I tossed their wheels and I am using robards. I fly off pavement though so I didn't increase the diameter.