Those [contact_points] are for PBY that don't have wheels. point.0 to point.3 are floats and the rest are scrape points.
Here are the contact points I made when I re-did the VN PBY-5A.
[contact_points]
//Gear
point.0=1, 10.08, 0.00, -4.1, 4200, 0.0, 0.69, 41.5, 0.1, 2.50, 0.70, 5.0, 5.0, 0.0
point.1=1, -6.91, -7.00, -4.1, 3200, 1.0, 0.69, 0.0, 0.2, 2.50, 0.88, 5.0, 5.0, 2.0
point.2=1, -6.91, 7.00, -4.1, 3200, 2.0, 0.69, 0.0, 0.2, 2.50, 0.88, 5.0, 5.0, 3.0
//Floats
point.3=4, 16.08, 0.00, -1.1, 6200, 0.0, 0.69, 0.0, 0.20, 2.50, 0.78, 0.0, 0.0, 2.0
point.4=4, 0.00,-20.10, -0.6, 6200, 0.0, 0.69, 0.0, 0.20, 2.50, 0.78, 0.0, 0.0, 3.0
point.5=4, 0.00, 20.10, -0.6, 6200, 0.0, 0.69, 0.0, 0.20, 2.50, 0.78, 0.0, 0.0, 3.0
point.6=4,-16.08, 0.00, -0.3, 6200, 0.0, 0.69, 0.0, 0.20, 2.50, 0.78, 0.0, 0.0, 3.0
//Scrape
point.7=2, 1.26, -50.0, 8.00, 10574,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,5.0
point.8=2, 1.26, 50.0, 8.00, 10574,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,6.0
point.9=2, -21.58, 0.0, 2.50, 10574,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,9.0
point.10=2, 8.83, 0.0, 2.50, 10574,0.0,0.0,0.0,0.0,0.0,0.00,0.0,0.0,4.0
static_pitch= 0.0
static_cg_height=3.68