You want the track to be almost even front and rear. The front suspension can be lowered by removing as much pre-load as possible from the shocks, and installing longer shock mount bolts top and bottom. With the shocks compressed, a length of chain can then be slipped over the bolts and held in place with a nut and washer. Ski carbides need to be removed and replaced with regular steel wear bars. Your stock track will be fine for getting started.
Studs are almost a necessity, and chisel points are best for grass.
I've found through trial and error that it doesn't pay to skimp on the proper parts. Any edge that you can gain on your competition will move things ever so slightly in your favor. Every little thing adds up in the long run. A means of cooling down your sled between runs is a must. To do this, you will need to build a cool down cart.