01 V702.4T Replaced TCM. Car in limp home mode

[Chassis]

Hi Everybody,
Here's the story (keep reading, you'll eventually hit the end )
A few months ago I bought the car as a project from an independent here in Sweden. They had replaced the tranny at a Volvo shop due to harsh shift, flare and delay N->D with no improvement and had given it up. After taking over I surfed all forums I could get a hold on. All symptoms pointed to the notorious AW55-50SN so I replaced it once again with a used one that I actually could test drive before buying. I've reset the adaptive memory performed the adaptive driving but the symptoms remain. Now when I've also replaced the TCM it refuses to shift and stays in D regardless if I try manual shift or put the stick in D. It sets check engine light and DTC P0602 but as I cannot erase it it might also set other ones that I'm unable to see with my simple generic scanner. THOUGH...there's no delay N->D
Any suggestion? New software? Any other trick?
Any help would be most welcome!!!
Greetings from Sweden.
Per

[mechaman1]

I have 2002 XC70 with bad transmission. I changed oil. It was dark with shiny metal flakes seen on sunlight. The transmission shifts in manual mode between 2 and 4th gears.
I saw that 2003 and later transmission are less expensive and plentiful than 01-02 models. They will physically fit in my 02 XC. I know they have slightly different 4.77/3.00/1.96/1.32/1.02 vs newer 4.66/3.03/1.98/1.34/1.02. I know if i install newer unit it may work but the TCM will detect incorrect gear ratio.
My question is: can I install TCM unit from 2004 Model? I've read that TCM is mated to VIN number. Will the transmission still shift on my car with 04 TCM and different VIN. How do you reassign VIN number?
On volvo parts site the TCM part number is the same for all years. If TCM swap is not possible can I load 2004 TCM software on my TCM unit in the car to reflect newer gear ratio with my VIDA DICE and three day subscription?

thank you for all answers