Hi Stuart,
I think the allen key fitment you are referring to is really called a 12 point head -- that is if what you have is a Toby-TAB. If you look closely on the head you will see "Toby $ TAB" engraved on the head.
Probably the only problem with a Toby-TAB in the Europe is finding tools to fit it. The size tool you need to fit it is based on the inch system, so common metric stuff won't fit. And even if you do have something that fits, good luck getting it in there if an automatic transmission is in the way!
Walt Tampa, Florida