That's one of the best colours on a Viva
I had a 4 door 1800 SL in that colour,but was rotten so used the running gear in my 2 door 1300L.
One issue I had was the inlet port on number four cylinder was choked up with carbon,
I couldn't get my little finger in there,it was almost closed up.
Had to get a headset and do a decoke,ran much better then.
Had a hell of a job getting all the carbon out,it was like coal mining.
I my experience the 1800 is a smoother running engine than the 2.3 too.
Best of luck with your project
Just one more turn should do it....