A 4 engined 737?! Boeing/Kawasaki 737-PXL:
This was a joint venture between Boeing and Kawasaki to build a 4-engined maritime patrol aircraft for the Japan Maritime Self-Defense Force. It was proposed in 1974 to replace the Kawasaki's licensed P-2 "Neptune" but Japan chose the Lockheed P-3C "Orion." and in 1977 Kawasaki began producing P-3C under license. The PXL was to have four 9,280lb, GE TF34 engines and a MTOW of 120,000Lbs with fuel of 5,270USG wing tanks and 1,250USG centre tank.
The illustration shows an extended and lowered nose radome and wing tip booms which are possibly MAD probes or other antennae.