The Kawasaki Ki-45 Kai 'Toryu' "Ni Shiki Fuku-sen" (Allied Code Name 'Nick') 'Bo' ('e') version was a little known night fighter equipped with experimental air-to-air radar "dempa hyoteki" (literally "radio wave target") installed in a transparent nose.
Non-standard armament consisted of a single forward firing 40mm Ho-301 cannon in the ventral tunnel. The aircraft may also have carried twin oblique dorsal armament but this is not confirmed.
It is believed that at least 12 aircraft were converted to this configuration at the Army Air Arsenal using a variation of the Taki 2 radar set. The exact configuration and appearance of the radar equipment is not known.
AFAIK no photographs of the Kai Bo have appeared. This rare and unusual Toryu was featured as a 1/72nd conversion from the Hasegawa kit by modeller Katoh Hiroyuki in the June 2001 issue of Model Art magazine (top picture). The type also featured in the graphic novel 'Who Fighter' by Seiho Takizawa, flown by the hero of the novel Lieutenant Kitayama (second from bottom picture).
Bottom image shows the exhaust flame pattern for the Ki-45 viewed from the rear at night. This is for the earlier single exhausts rather than the multiple thrust type of the late production Kai Tei.
Image credits: Model photograph: Model Art & Katoh Hiroyuki © 2001; Profile plan: Model Art © 2001; Comic: Dark Horse Manga & Seiho Takizawa © 2004