I tried that, no deal. They have to go into the spark plug hole about 1/4" or more above that point.
Best thing I think, is to cut off the bmw rubber cover part and slide it over the wire. High temp silicone could be used to seal it to the Volvo wire if so desired.
One other thing i thought of, would M10 wires be an option? the boots are straight and don't have the 90* angle on the back so they should go straight into the spark plug holes right?