Yeah nicky , Understand .
I just look at it a little different . I don't see any problems with the modifications you made on the D8 & D5 if it made it more operator friendly or added some safety value .
Did your welding cause any structural problems to either machine ?
Myself , I have lost count of welding modifications done for customers & myself on trucks & equipment .
One job that comes to mind is when my logger buddy bought a 225 Timberjack skidder . He had lost his older brother in an accident and wanted to prevent it from happening again .
So we welded in heavy mesh screen on front , built a side door with mesh on top & sheet steel below . All got welded rite in to the ROPS frame tubing . Wish I had a picture of it but it looked something like this . Worked well for them .
Just look ... Don't touch it as the paint is still wet .
If you were to bring me a new 2016 model Cat D8 with a complaint about operator comfort , safety or special purpose that the dealer won't take care of I will gladly fire up the torch , & flip on the welder to give the customer what they need .