Centering a Grid between page margins

I have several sets of data that I want to display in columnar form. Each set of data is in a Table and will display with different number of columns.

Is there an easy way to center each set of data so it appears centered between the page margins?

So far, I display each set using something like Grid Grid Table… The inner Grid creates the columnar form, and the outer Grid displays the column form in the center position. I end up with something like this:

But even this requires that I manually size the Spacings of the outer Grid. I’d rather avoid the outer Grid and just center the columnar form between the page margins.

Thanks for any suggestions.

I’m still looking for a way to do this with one Grid, but a partial solution is to use ItemSize to avoid manually sizing Spacings in outer Grid.

(* Eight data triplets  *)
data1 := {{0, -2, 14632971213167*^-14}, {0, -1, -84548187169114*^-14}, 
          {0, 0, -37563603672040*^-13}, {0, 1, 33855169168385*^-13}, 
          {0, 2, -95791963387872*^-14}, {0, 3, 15772038513228*^-14}, 
          {0, 4, -16616417199501*^-15}, {0, 5, 81214629983568*^-17}}

(* Create a table of the data w/ header row *)
tbl01 := Prepend[
  Table[{i, data1[[i]][[1]], data1[[i]][[2]], 
    NumberForm[N[data1[[i]][[3]], 14], 14, 
     ExponentFunction -> (If[(# + 1) == 0, "", (# + 1)] &), 
     DigitBlock -> 3, 
     NumberSeparator -> "[ThickSpace][ThickSpace]"], i + 4, 
    data1[[i + 4]][[1]], data1[[i + 4]][[2]], 
    NumberForm[N[data1[[i + 4]][[3]], 14], 14, 
     ExponentFunction -> (If[(# + 1) == 0, "", (# + 1)] &), 
     DigitBlock -> 3, 
     NumberSeparator -> "[ThickSpace][ThickSpace]"]}, {i, 
    4}], {Item["i", Alignment -> Center], 
   Item["!(*SubscriptBox[(I), (i)])", Alignment -> Center], 
   Item["!(*SubscriptBox[(J), (i)])", Alignment -> Center], 
   Item["!(*SubscriptBox[(n), (i)])", Alignment -> Center], 
   Item["i", Alignment -> Center], 
   Item["!(*SubscriptBox[(I), (i)])", Alignment -> Center], 
   Item["!(*SubscriptBox[(J), (i)])", Alignment -> Center], 
   Item["!(*SubscriptBox[(n), (i)])", Alignment -> Center]}]

(* Display the data as a grid *)
tbl02 = Grid[tbl01, Alignment -> {{{Center, Right, Right, "."}}}, 
  Spacings -> {{0, 1, 1, 1, 3, 1, 1, 1}, Automatic}, 
  ItemStyle -> {Directive[FontFamily -> "Times", 
     FontSize -> 14], {Italic}}, 
  Dividers -> {None, {1 -> Directive[Thickness[1]], 2 -> True, 
     6 -> True}}]

(* Center between margins by displaying as a grid in a grid *)
Grid[{{tbl02}}, ItemSize -> Scaled[1.0]]

The result is