IMHO that's just way too much crystal malt (18% currently). I'd eliminate the 120L altogether, and reduce the 60L. The extra dark crystal will contribute raisin, fig, prune, even tobacco flavors that I wouldn't want in a bock.
For IBU calculations, I like to use Tinseth: http://www.realbeer.com/hops/bcalc_js.html
Assuming the Goldings are 3-4% AA, use 2 oz at 60 min. That will put your IBUs in the range you want. I'd steer clear of Nugget in this style.
Fermenting at 50°F for the entirety of fermentation would be good. If you like you can raise it into the high 50s or low 60s once it's within a few points of FG (a diacetyl rest). If you pitch a proper amount of yeast it shouldn't be needed. Which brings me to...
If you want to use a single pack of yeast, and you don't have a stirplate, you're looking at a gallon starter MINIMUM. To get to a standard lager pitching rate, you'd really need two packs in a 3 qt starter, and frequent shaking (no airlock!). Check out http://www.mrmalty.com/calc/calc.html
Welcome to the forum, by the way. Looks like you're on track to make a great first lager.