So I have a great Iv Breed, Ev trained Spiritomb. I'm using it as special wall and is moveset is my greatest concern.

-Sucker Punch
-Will-O-Wisp
-Pursuit
-Pain Split

Holding Leftovers

I'm thinking of switching out Pursuit for Protect and POSSIBLY Will-O-Wisp for something else. just don't know what. can anyone help?

Where is the EV spread?

I got it in a trade, I don't know, but it was fully EV trained for that purpose.

IV's:
31/31/31/x/31/x

The current moveset is good. You do NOT want to take off Pain Split and Will-o-Wisp, they help you survive physical threats like Weavile and Tyranitar a great deal. Although, Spiritomb is not mainly used as a special wall, it has the Base Special Defense, but its HP is terrible. Spiritomb's main use is for switching into Psychics and trapping them with either Pursuit or Sucker Punch.

The only other alternative to Sucker Punch or Pursuit would be Taunt, but since he's very slow at using it, stick with what you have. Preferred EV spread and nature are:

Careful @ 252 HP/140 Atk/116 SpDefense

This grants you 304 HP, 280 Attack and 281 Special Defense (if you have 31 IVs in those stats).