Hefe Weizen Partial Mash

I am planning on trying out a partial mash recipe. I found out that my water (tap + 1/2 distilled) is perfect for paler type beers and since I really like wheat beers, I figured this would be the time to try it out. I will be using the counter-top partial mashing method mentioned here:

http://byo.com/feature/1536.html

I will be using a 2 gallon cooler, mashing approx 4 lbs. of grain to test this out. So, I took an extract recipe for a hefe weizen and converted it to a PM. Here is the recipe. Please critique it for me!!!

Batch Size : 5.25 gallons

3.75 lbs. Briess Wheat DME
2.00 lbs. Pilsner malt
1.65 lbs. Wheat malt
0.35 lbs. Munich malt

1.25 oz. Hellertauer Hersbrucker (60 min)

1 pack #3056 Wyeast

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Some questions about the grains: how difficult or long will it take me to crush the grains using a rolling pin? I have never done this before, so I am nervous about it.

I am planning on using about 1.25 qts. of water per pound of grain for the mash. Then I will use about 1.5 to 1.75 qts. of sparge water. Is this correct? I only have a 3 gallon brewing pot.

I can't speak to the rolling pin, but I'd guess it won't be that much fun.

On the plus side I think your numbers and recipe look really good.

No way on the rolling pin; I did two pounds on my last batch, absolute PITA and a mess. Get the malt pre-milled.

Make sure you put a blow off tube in place of the air lock on the fermenter. I learned the hard way on this one.