Wee Heavy process questions

I have all the ingredients for a Wee Heavy and am wondering if the following process would be worthwhile.

Using a PM technique:
Mash grains and take the "first runnings" into one pot and begin to boil/concentrate this down.
Sparge grains into a separate pot then add the concentrated wort to this pot for the remainder of the boil.

If so, when does the boil time for hop additions start?
How much should I boil the first runnings down prior to combining the two volumes?
Is this going to add anything to the beer or just make the process take longer?

Recipe (in case it matters):
5.5 lbs light DME
4 lbs MO
1 lb Crystal 60
.25 lbs roasted barley
.1 chocolate malt
1 oz Brambling Cross (6%AA)
1728 yeast

Kettle caramelization was the traditional technique for brewing Wee Heavy/Strong Scotch; I usually reduce the first runnings by half. Doing this adds rich caramel/toffee flavors to the mix and, in traditional formulations, replaces any crystal malts in the grist. Wonderful Wee Heavies can be made using nothing more than pale malt and roasted barley to adjust for color and the kettle caramelization.

Add your hops at 60 minutes as usual and the reduced first runnings when convenient to you.

Thanks for the advice. Brewed and fermenting away.

Certainly!

Just remember to keep this one cool during fermentation (I ferment at 58° for this strain) and lager after primary if you are set up to do so. You'll be rewarded with a malty and satisfying ale and a very clean yeast profile.

I have the fermenter at ~60*. The last time I used this yeast I was at ~55* and was happy with the results.