Stripped bolt - please help (Houston)

[Greta]

Two questions for you experts:

1. In the midst of a very tedious brake job we have managed to strip a couple of the allen bolts that connect the front brake rotor and hub on our '82 240D. The guys at Bap Geon (our local import auto parts store) told us it would be sufficient to use 2-3 bolts instead of the original 5, as long as the bolts were symmetrically spaced. Is this the case? Have any of you ever used less than 5 allen bolts?

2. If using less than 5 bolts is insufficient, does anyone in the Houston area have any spare bolts that would work?

Thank You!