Switching to front disc brake questions

Ok. On my 64 Dart, I am switching to front disc brakes, at the recommendation of several people. Reason is because that this will be a daily driver, it really needs to happen.

I have purchased a Wilwood kit to go on the stock spindles. This one:
Wilwood Disc Brakes - Front Brake Kit Part No: 140-11022

Currently it would appear that the Dart has the stock single reservoir master cylinder, which the line runs to a block down low in the bay and splits off from there. (see pics)
From the reading I have done, I really need to get a dual master cylinder with adjustable proportioning valve, correct? As well as brake lines from one reservoir to the discs.
Does anyone have a recommendation on which to use? Should I just go to the junkyard and find a dual that will fit, or get a new one?
Once installed with the adjustable proportioning valve, set it so that the front brakes lock up prior to rears.

Am I on the right track?

Thank you all!

OH, and while this pic is here, what the heck is that silver device with the hose coming off it to the right of the master cylinder and steering?

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