14L Detroit DDEC VI to 12.7L at inframe time. Is this even possible?

OK, my 2008 Cascadia has sunk liners, which blew the head gasket. This is a 14L EGR DDEC 6 Detroit Series 60 engine, ESN 06R0994171. Mechanic is suggesting new liners and pistons, well an inframe kit to be safe. The head is toast but I can get a reman 14L head for $2,850 exhange. The ONLY DEEC VI heads available for my engine is a Detroit OEM reman, BTW.

PROBLEM: I have always lusted after the 12.7 L pre EGR engine but since the engine needs an inframe now, how hard would it be to simply buy a 12.7L inframe kit and a reman 12.7 L crankshaft but leave the rest of the engine alone? I realize that the ECM probably won't like the lower displacement but I want to get a PDI or full tilt exhaust manifold and BW 171702 anyway. Later on.

For now, I want to know if buying a 12.7L inframe kit will fit my 14L DDEC block. The 12.7 inframe kits are cheaper, too by about $400.

 

Thank you for your super quick responses.

 

I keep reading that the 12.7L can put out 500 HP and 1650 ft-lbs of torque just like the 14L but using less fuel. I gave up on this idea because the cost to convert it properly is just too much. I ended up inframing my existing 14L DDEC 6 engine and putting on a reman head.