I found this in my moms Stevia cookbook. I guess you could convert the Stevia to Splenda, I dont know how though?

Filling:
2 eggs
9 tsp. stevia blend
3 tbls. lemon juice
1 tsp. lemon flavoring
4 tbls. butter, melted, cooled
1 tbls. grated lemon rind

Topping:
4 oz. cream cheese, softened
4 oz. sour cream
1 tsp. vanilla
1 tsp. stevia blend

Crust: (Im putting this in here, maybe you guys can convert it, or just use your own crust? I was thinking about not using a crust at all)
5 tbls. butter
1 tbls. stevia blend
1 cp. flour

For crust:
In a bowl, beat butter and stevia till fluffy. Beat in 1 cp. of flour till mixture resembles course crumbs. Press into bottom of an ungreased 8x8x2-inch baking pan. Bake in a 350 oven for 15 minutes or until golden brown.

Topping:
Whisk all ingredients together. Set aside.

Filling:
Beat eggs and stevia; mix in lemon juice, lemon extract, butter, and lemon rind. Pour mixture into hot baked crust. Bake at 350 until lemon filling is set (about 20 minutes). While still hot, spread with cream cheese topping. Allow to cool, cut into squares. Makes 20.