The C-172, N49231, had just departed RWY 32 at Harvey Field, an uncontrolled airport, on an instrument training flight. Radar data shows that the C-172 was climbing out at 700-800 fpm at 65 kts and on a true heading of 310 deg. The BE-J35, N66QB, had departed earlier from Payne Field at Everett. Radar data shows that the BE-J35 was in level flight at 130 kts and on a true track of 280 deg. The collision occurred at 1,600 ft MSL in uncontrolled airspace. The cabin top and left wing of the high-wing C-172 displayed linear scratches, gouges and paint smears which matched the impact damage, scratches and gouges found on the bottom surface of the left wing of the low-wing BE-J35. Official sunset was 1 minute after the accident; the sun would have been 0.01 deg above the horizon at the collision altitude, and at a true bearing of 284.6 deg from the accident site. Witnesses reported dusk dark light conditions on the ground.