Just a little elaboration on the track inserts post. You'll probably need to click on the image to see the large view, but this is an end shot of the 4' Ocean Boulevard street panel. Basically, the track is attached directly to the panel with pins and glue, and then 1/8" foam sheet is used to bring the base for the street and sidewalk nearly up to the level of the rail head. The road surface is a layer of 0.010" styrene brought close to the rail head and glued to the foam. The sidewalks on either side are 0.040" styrene, and the curbing is 0.040" x 0.020" strip. On a track strip, those inserts are inserted between the rails, and between the track strips I've inserted a length of 0.040" styrene sheet. Although, in retrospect I'd now probably use 0.030" because I've had issues with streetcar wheels riding up on the centre strip.