TLB...some interesting vessels, however one on I cannot fathom

is the twin shaft drive
Two x twin motors, each pair to their own common gear box and single output shaft....with each opposite ended motor of the same rotation which by mounting reverses the actual rotation .....is this why each motor has a common direction arrow?
We see what appears to be a common setup angle between motors 2 and 4, but the belt angle from motor 1 is different

?
Each motor to gearbox toothed pulleys appear as 1:1, however the output below No 1 motor suggests a step up ratio to the propeller shaft......or is it just an illusion?......Derek