Ok, here is the problem:

I have a 3-wall tub alcove that is 66″ long but a jog in the wall makes it only 32″ wide.  Tubs I have found that fit these dimensions are horridly expensive (particularly because we would like to get a whirlpool style).  We found a tub we like that is only 60″ long but is 34″ wide (we will box in the extra 6″ to make a shelf).  We thought we were home free (ha ha) but the tub is a drop-in style tub and the alcove also functions as the shower. So…If I frame the tub in, is there a way to butt the tub against the wall and prevent the water from pooling on the enclosure outside the rim?  Basically I need to convert a drop-in style tub into one with a tile flange for an alcove.  Any advice you can give would be fantastic!

          _______________________66â€________________________
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         |                                       Tub                                                    |
 32† |                                                                                                  |
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         ———                                                                                       |
             6†  |                                                                                       |
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