Do I need to buy new bolts?

[D'Marco]

I've decided to buy a set Sparco Assetto Gara alloys and was wondering if the Bellone bolts will fit? The Sparco bolt seats seem to be conical and for the life of me, I can't remember if the Bellone ones are or not!

If I do need new bolts, what length do I need to get? I know they're M12 x 1.25 but the set I'm looking at on eBay are offering various shaft (ooo errr ) lengths.