I've never run or even seen BBM heads, but if they have an efficient chamber that doesn't need a lot of total advance, you want a very fast advance curve. So if you only need 34 degrees total advance, I'd use the one of the quickest bushing/spring combinations with the MSD distributor. I think the black bushing has 18 degrees of advance. I'd use that. Set your initial timing based on your total. So you if you need 34 total, set the the initial at 16. Depending on your combination you can choose springs to bring in the total when you want it. I'm guessing you want it pretty quick, say in the 2500-3000 rpm range.
JMO,
paulie