So, I did some further investigation and I came across a YouTube article by Barton Dring:
His explanation of “Understanding G-code Coordinate Systems” is superb:
I changed my settings from the earlier suggestion of:
G10 L2 P1 Xval Yval
to
G10 L20 P1 Xval Yval, where I eventually set Xval and Yval to 0.
Now, after homing my X-carve, my Origin is the same as the home position:
$#
[G54:-249.000,-249.000,-1.000]
[G55:0.000,0.000,0.000]
[G56:0.000,0.000,0.000]
[G57:0.000,0.000,0.000]
[G58:0.000,0.000,0.000]
[G59:0.000,0.000,0.000]
[G28:0.000,0.000,0.000]
[G30:0.000,0.000,0.000]
[G92:0.000,0.000,0.000]
[TLO:0.000]
[PRB:0.000,0.000,0.000:0]
ok
?
<Idle|WPos:0.000,0.000,0.000|FS:0,0|Pn:P|WCO:-249.000,-249.000,-1.000>
ok
$G
[GC:G1 G54 G17 G21 G90 G94 M5 M9 T0 F6000 S0]