Coordinate Array distance & move distance

[nextvkin]

Hi all,
I have a db of a chain and it has a rod attached to the end link. I want to stretch the chain (array) so that the rod always stays attached to the end link. I've given it a move action. What I want is to be able to do it in one action rather than 2. Can someone have a look (attached) & help? Thanks.
Kay

I've worked it out.

[jb.burdy67166182]

Thanks for posting, it was a lot simpler than what I was trying to do...