Thank you everybody for watching and kindly commenting.
I have prepared the "nest" for Viper - two cabane lines had to be tied and two oil pipes from the oil tank added - they will be barly visible later but who cares...

The exhausts required a surgery - the first and fourth inlets had to be gently cut out and moved off the internal second and third ones - the spacing of holes in Roden's Viper cylinder blocks was not the same as in WNW Hisso. There is still some cleaning of the filler CA glue necessary there as can be seen in the photos. They were put into place temporarily to help in positioning of the engine.
Viper itself got the last missing bits from Roden's box and some grime not too look too fresh in 1920



And then luckily it jumped into its place without any collision!


And with the freshly painted radiator put on to get some taste how it will look like later.

