Why are you being so mean and insulting to the OP?
What you actually wrote was:
There seems little doubt, looking at the many photos of Viscounts on the Net, that the thrust line is not the same on different marks of the aircraft.
......which is vague and does not answer the OP's question, which was:
Looking closely at photos it appears the engines have a negative angle of somewhere around 0.5 to 1.0 degrees on most models. Some later aircraft appear to have the engine parallel to the fuselage waterline, such as V 808 (G-BBDK) and V 806 (G-AOGY).
I can’t work out if this is an optical illusion created by the shape of the cowls, or whether there was an angle to it.
I am currently working on a detailed drawing of the Viscount 700 & 800.
Hoping someone can set me straight.