I'm going to buy a NYC Niagara 4-8-4, take off the smoke deflectors and change the front truck and make a Pittsburgh & Lake Erie 2-8-4 Berkshire. Has anyone attempted this before? If so does anyone have advise?
Um, well right off the bat, the Drivers on the Niagara would be much too large for the P&LE berk. You'd get better results by taking a berkshire bachmann already offers and crop a niagara boiler on that.
The Niagara's running gear setup wouldn't look right either condering it's primarily a passenger locomotive, the main rod connecting to the second set of drive wheels, and the berkshire connecting to the third set of drive wheels
It would appear that one would have to take a course out of the Niagra boiler to fit it to a 2-8-4 mech. I agree that using one of the Berks as the mech basis is the way to go. I would also note that the P&LE Berks had a rather unique all-weather cab that the Niagra doesn't.