It's a big pain and even th odd two or three who've done it have mainly concluded it's not worth it.
Currrently we still have the old low and higher powered moped type approval and SVA rules in force, but they are currently due for change into the new L1e-A and L1e-B classes. The new type approval rules for those are not yet in force but should mostly be by January 2017. Since they will also affect SVA, it's probably worth waiting a while, since I know there are some easements of requirements in L1e-A so may also be for the full moped class L1e-B.
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