Hello everyone, first post!

I have a Lionel 2026 engine with tender (the earlier 48-49 version) and Pullman cars that my grandfather bought around the time my dad was born.  We inherited this when he passed and my being the engineer in the family I became the defacto owner considering the last time it was running was about 20 years ago when I set it up (in high school) and got it working pretty much by trial and error.

I still have it all in boxes and am planning to start getting it up and running again, this time going through and cleaning/repairing everything properly to get it nice and neat. 

First thing I'm finding is more of a basic question though: Its running off a 1044 transformer and the power cords back then were not quite what they are now.  I think there is an end plate missing around the prongs, leaving some internal components of the plug exposed.  They would be flush against the wall when plugged in, but for peace of mind I'm thinking I would like to just replace it.  I haven't taken the cover off yet but from some of the schematics it looks like a pretty simple soldering job where the cord connects will do it.

Anyone know if using a modern 3-prong plug would create any issues with the transformer?  I've never actually done this before, though I've done plenty of basic soldering.  If this is fine, wouldn't there be a 3rd wire for the ground to connect and does anyone know where that should go?  I don't know enough to say if simply hooking up to an internal frame or the metal base plate would be enough, or even safe...

thanks!
Leigh