On November 27, he and his wingman, Lt. Robert York, became embroiled in a seemingly one-sided dogfight - the odds were 50 to one! Wetmore quickly called in help when two more gaggles of 100 fighters each were sighted. Unfortunately, the rest of the flight had aborted with engine troubles, so Wetmore and York stalked the massive force alone. When the enemy saw the size of the opposition, the hunters became the hunted. "We had to attack in self-defence." Wetmore said later.

With little choice remaining, the P-51s waded into the fighters, and they quickly reduced the odds by one apiece. A good burst with a 20 degree deflection shot brought Wetmore's second kill. He then turned into the attack of another Bf-109, and the pair twisted and turned as the respective pilots strove for the upper hand. Wetmore finally got the advantage, and shot off all his ammunition, whereupon his foe bailed out. Now defenceless, Wetmore bluffed for another ten minutes before extricating himself from the melee.

He followed this up with another big score on Valentine's Day 1945. Vectored by ground control onto enemy fighters near an aerodrome west of Dummer Lake, he sighted four FW-190s flying in line below him. He dived and shot down the last FW-190 in line. Firing at a second, he saw the pilot attempt to break and dive, but he had no altitude and snap rolled into the ground. Shooting down a third FW-190, Wetmore called to his wingman to take out the last one. Shots were exchanged before a fogged windscreen ruined the pilot's aim, and Wetmore finished off the German. Reforming to attack other FW-190s, a new P-51 joined the fray. Wetmore and the newcomer opened up, and both German pilots bailed out. Wetmore was credited with four downed and one shared.

For his final kill on March 15, he shot down the fourth and last Me-163 Komet to fall to the guns of Eighth Air Force Mustangs. Operating around Berlin, Wetmore spotted two Me-163s and he closed to 300 yards, amazed as he watched one of the rocket-fighters zoom upward. He followed as well as he could, and at 20,000 the Komet's engine flamed out. The Me-163 split-assed and dived, with Wetmore on its tail. As his ASI indicated over 600 MPH, he opened fire at 200 yards. His strikes chopped away part of the German's wing and the pilot took to his chute.

Wetmore was the highest scoring 8th AF ace in 1945. He continued in the USAF after the war, only to die when his F-84 crashed in February 1951.