Updates / Backdates

1st post here, so I probably screwed up and put it in the wrong place. but here goes. Has anyone ever tried or seen any of the following conversions; or are they even possible:

Update Tamiya 1979 Williams FW07 to a 1980 Williams FW07B
Backdate Tamiya 1982 Brabham BT50 to 1981 Brabham BT49C
Update Tamiya 1986 Williams FW11 to a 1987 FW11B
Update/Backdate Tamiya 1990 McLaren MP4/5B to a MP4/5 or MP4/6
Update Tamiya 1990 Williams FW13B to a 1992 FW14B
Update Tamiya 1998 McLaren MP4/13 to a 1999 McLaren MP4/14

1st post here, so I probably screwed up and put it in the wrong place. but here goes. Has anyone ever tried or seen any of the following conversions; or are they even possible:

Update Tamiya 1979 Williams FW07 to a 1980 Williams FW07B
Backdate Tamiya 1982 Brabham BT50 to 1981 Brabham BT49C
Update Tamiya 1986 Williams FW11 to a 1987 FW11B
Update/Backdate Tamiya 1990 McLaren MP4/5B to a MP4/5 or MP4/6
Update Tamiya 1990 Williams FW13B to a 1992 FW14B
Update Tamiya 1998 McLaren MP4/13 to a 1999 McLaren MP4/14

It all depends on the level of detail you want and how much you are willing to make yourself. I'd say that the FW07 and FW11 jobs are straight-forward and the FW14 would be very difficult. As for the rest, I don't know. It really depends on your skill and your references.

Bill