Is that 32" inseam an accurate cycling inseam, or a pants inseam? Thre's a big difference. If your inseam is only 32 inches or 81cm, then you have short legs for your height. You might want the longer reach of a larger frame, but the height of it should be too great.

What's more important is your actual saddle height. With an 81cm inseam, your saddle height may be around 71cm. If it's a lot greater, then you're probably talking about a pants inseam and your cycling inseam is longer.

Keep in mind that sizes between brands rarely match up and even the same size of different models of the same brand can vary by 20mm in stack height.

Comparing the 56 and 58cm sizes of the Trek 1.5, either one could be setup to fit the same. The smaller frame would require a stem that's nearly 20mm longer and 20mm more spacer (and/or more stem angle) to get the same bar height.