new bridge inside old bridge

Since the current girders are spaced for standard gauge, what is the feasibility of placing steel girders at narrow gauge spacing in between the existing girders to preserve the appearance of the bridge. (Someone, in another post, stated that due to the standard gauge spacing of the girders, the ties had to be double size to span the gap and support the engines.) A railroad crane could be used to install the new girder assemblies similar to what WP&Y used.

A second method would be to bring in two/three/four 12" by 24" 310 foot long steel I-beams on flat cars. (Steel is flexible, welded steel rail segments are 1/4 mile long and are dragged off the flatcars as needed.) At the bridge site the I-beams would be sitting on skid plates or rollers on the cars on the west side. With skid plates or rollers on the bridge one of the engines on the east side could pull the I-beams onto the bridge with a steel cable. Incremental cross-brace removal and lowering the I-beams into place then new cross-bracing and attachment to the existing bridge structure would preserve the historic appearance and fabric of the old without compromising strength and safety of the new. ----jim----