If you want a DD Samurai I would start with a lower base unit. There are quite a few in the Seattle area right now for under 2K that look pretty nice, and 4k is a lot of investing.

My Tracker is a great DD, gets 25mph with the 235/75 R15 tires. It used to get 27 with the old engine, has more room inside and a lot more creature comforts.
For a Sammy DD/Adventure build I would go with some 30" tires, a 1.6L and 2.5" OME springs. There are quite a few Sammy's running this build and they can go anywhere. Some lockers and you are set for anything other then tire size obstacles.