Re:
I very basic terms yes, at least it will be pretty similar.
Some of the reach depends on the bars. I have a Basso which has the same top tube length and stem as my other bikes, but the bars are a different shape, making the overall distance to the hoods longer, so watch that.
If you can get the front of seatpost to centre of stem distance similar, then I think you'll have a perfectly rideable bike.
I'm sure this is not how the multi million pound 'bike fit' industry go about their business. :mrgreen: