Steam...

[Sumpter250]

SP Daylight 4449 saw some run time in BNSF paint on BNSF rails. It is also a 4-8-4.

I have to ask, it did?, in BNSF paint?, because the BN and SF merger is very recent, and I thought 4449 had been retired before that.
CB&Q, WP, SP&S, and what ever other fallen flags that became BN would also be valid choices for road names. The fallen flags would have been more likely to have operated steam. I'm probably wrong, but I don't recall the BN as having steam in operation.