Hi there *^^*
I was in the same situation as you just a couple of months back...except that mine was from 1.5 to 2.0cc.
Regretted a lot cuz if only i had registered my engine last year, it would have made my life MUUUCCCCHHHHH easier.
I asked around like 10 runners and all of them turned me down.
One claimed he could do it, paid my deposit, but it was rejected.
HOWEVER!! I found a runner who could do it, and now, i proudly drive my car around with an original road tax *^^* kaka couldn't be happier than now!!
If you're interested, let me know and i will give you the guy's no.
just tell him, the korean girl driving satria introduced *^^* Don't have to take the car for inspection as well ^^;
BUT, just for your info, i paid a FAAAAAARRRRKKKKKING shit load of money to this guy :( reallly extremely hard to get approval nowadays. everyone told me it was impossible!!
so, just make sure you have a lot of cash ready for the registration, if not, i think changing your engine to a 1.8, either 4G93 or 4G67 could be a better option ^^; yes, it costed THAT much :(
so, good luck bro..cheers!