riddle - Tokyo Metro puzzle #2

This is similar to the previous one, however they are independent. The map is here.

Here is the riddle:

From the best of interchanges
Lies a station you must seek
To the East-West you must go

Don't be grumpy, be positive!
The Japanese bridge'll be waiting for you.

Now take the route to the gold
Till you descend upon the loop.

Now which station are you at? Check!
It should be on the loop, I say.
And it should be near a JR line.

Good luck during your Metrosurfing!

Hint:

In Japanese, "Japan" is "nihon" and "bridge" is "bashi."