I'm aware that we already have the F45 in-game, with reskins available on various websites, but the FP45 IS a different animal that was originally built for different purposes, but that does mean one could take the current F45 model and use it as reference whilst making a new, high quality FP45 model, and have it available in the various liveries and configurations the FP45's have had throughout the years, from the Santa Fe to the Wisconsin Central, with and without gryralites, with and without simulated steam heat, and for what-if scenarios, have Amtrak liveries with both properly simulated steam heat and head end power plugs and cables and proper HEP simulation. Granted, this might be asking for a bit much, but hey, we've seen some pretty advanced things come out for Train Sim in recent years, so I think having something that's quite possibly around the level of Armstrong Powerhouse's Class 68 Enhancement Pack IS doable. Why, the majority of sounds could either be recorded directly from any of the operable FP45's in preservation or one could work with Searchlight Simulations to use their 20 cylinder EMD 645 sound pack as the majority of sounds for the locos, with any other needed sounds being added in. Now, in regards to the passenger cars, it'd be nice to have some Santa Fe passenger cars that the FP45's would've pulled in regular service, from RPO's and heavyweights all the way up to the hi-levels and transition cars they pulled on the El Capitan and Super Chief. Granted, the whole deal with BNSF being nitpicky about logos and all that jazz would end up being a problem, but one could negate this by leaving the models unbranded and all, but then that leaves the branding up to reskiners and there's most likely people out there who don't like dealing with installing reskins, but hey, their loss.