Interior can be changed if you have parts from Evo X halfcut dashboard. I can see that the RPM/Speedometer gauge is different. The gear stick is also different with the TC-SST. Unless you are using Inspira manual which can mimic the manual Evo X gear stick.
But still, credits still goes to the owner who spent so much effort and money in converting his Lancer GT.
He might have the money for the conversion (which the total cost might be same as a recond Evo X) but you forgot about the maintenance of a real Evo. It is way more expensive compared to the maintenance of Lancer GT. I'm talking about turbocharged engine VS NA engine, FWD VS 4WD, CVT auto VS double clutch gearbox (unless he gets a manual), fuel consumption.