Age of engine?!?

[Eternal]

Hello all!
I have a little problem and could do with some advice!
So i have an engine from around 1999-2000 how hard do you guys think it would be trying to get it past current emissions?

I have two options:...
1) Try to get past current emissions and aim for a new vehicle reg.
2) Get letter from Nissan stating the age of the engine and go for a Q plate with easier emissions test.

The other issue i have is no one at Nissan can seem to produce let a letter of age from just my engine code.... Bugger! Anyone know anyone at Nissan that can help?

Thanks!