Magnum 360 heads "best" for my build?

That is a very good looking rocker setup... Just what the RHS/Indy's NEEDED. As far as the cam... Comp probably thinks the XE268 will have problems with the stock valve/spring package and 1.6 ratio rockers (comes to .512 lift at the lifter... prob closer to .490 in reality at the valve but they don't want to risk it). So they gave you basically the XE262 spec lobes.