I just finished up my 23rd diesel loco conversion to fixed pilots and full length handrails that have the capability of having either 3-rail or 2-rail wheel sets. These are not easy to do. Most, if not all 6-axle diesels locos are going to require the use of a bench grinder to remove alot of the inner portion of the pilot as there is too much metal to allow the truck to swing.
However, I've figured it out and will post some "how-to" pics soon. I do 3 at a time to keep it rolling. Tichy train group sells the correct brass wiring to use as handrails (.025" brass) Also most of these diesels are 4mm between the top of the pilot to the bottom of the frame/shell so you can use 4mm plastruct strips ion various thicknesses, depending on the size needed. I made a jig to use for drilling holes in the pilots to attach the pilot to the pre-drilled holes MTH put in the shell. This makes it a perfect fit.