Hi, ED
try this ,process each dxf into a finished tap file. then with mach3 open use the text editor to combined the two files using the copy/paste function. make sure to remove the M30 end of file command that will now be in the middle of the new file and do a G00 move
to connect the two files, then do a save. open up lazycam then import from mach3 ,they should now be combined so you can finish it the way you want. do what CHIP ask you to do and post your DXF and we will see if we can put them together for you.
bill