How about an adapter kit to install all the 450 tanks and nav gear onto a 690?
A guy in the US has built such a kit to fit all the 450 gear onto the 690 without any frame mods: https://www.facebook.com/groups/1036987323048228/permalink/1514311408649148/
Next project!
Any link besides facebook?
No Sorry. He has offered the cad files for the parts to people for free as long as they are not going to sell them. You could contact him and ask for them.