1/2" blue foam was placed on the white "risers" to make them wide enough for the base of the trestle. Later this form would be augmented with cardboard strips and other pieces of foam to give the trestle site a more realistic contour. White glue was used for all of the foam and track gluing. Remember that the trestle bents are just being fitted at this point and cross members must be added before the bents are permanently installed. Once the trestle was in place some CA was flowed between the trestle deck and the tie strip for permanency. The trestle assembly was done with Faller plastic cement.
These two photos show how the foam "land" was removed and the bents are fitted to the site. Various slices of foam and other materials were used to simulate the bent "foundations" and make the supports fit so that the trestle deck would be level (Actually there is a very slight grade on the trestle but the deck lays in a straight and even line relative to the horizontal. It follows the original flex track as it was before the roadbed was removed. All this fitting is a bit tedious but it is not difficult. In the photo to the right you can see where the "river bed" has been removed from the white foam layer over the plywood (Don't use the white stuff! Use the blue or pink stuff!) I was careful not to shorten any of the bents until I had made certain that they would fit and that the bridge deck would be uniform in height.