Boosted Indy Specialties motor ..... That's where it's at. :face-icon-small-sho
BD, Silber, HM, Twisted, Turbo Perf..... A lot of kits to choose from. A very wise man told me "doesn't matter what kit it is, none of them are perfect". Pick what's best for you. They are all different. I think some run a little better than others, but not going down that road.
AK ... IndyDan can cut your stock head to accept different domes. I suppose technically it is still switch out. It just nice you can switch domes and rest remains stock.