Looking good - real good.
Incidentally, about that cab/firebox gap - I'd take some styrene sheet - bent to conform to the tab at the end of the firebox, with some reinforcement square styrene run under the firebox if necessary - before I lengthen the cab. The bottom edge of the cab looks to be just about the right length as it is already, if not maybe a few (insignificant) scale inches longer then the prototype.
That said, there is nothing more distinct about that boxy Q2 firebox then it's length from cab to it's taper - it would be a shame not to lengthen that Lionel Atlantic firebox to take full advantage of that feature of the prototype. Just wouldn't look right any other way, IMHO. Then again, I'm also a rivet counter
Best of luck!
-Kurt
Incidentally, about that cab/firebox gap - I'd take some styrene sheet - bent to conform to the tab at the end of the firebox, with some reinforcement square styrene run under the firebox if necessary - before I lengthen the cab. The bottom edge of the cab looks to be just about the right length as it is already, if not maybe a few (insignificant) scale inches longer then the prototype.
That said, there is nothing more distinct about that boxy Q2 firebox then it's length from cab to it's taper - it would be a shame not to lengthen that Lionel Atlantic firebox to take full advantage of that feature of the prototype. Just wouldn't look right any other way, IMHO. Then again, I'm also a rivet counter
Best of luck!
-Kurt