... But if you're saying what I think you're saying, why don't you 'block-out' the 2" (with a 2" piece of wood), and bold as you normally would? This would give you a SOLID surface all the way 'through'. Of course, use Pressure Treated wood since you won't be able to maintain the 2" as you would a fully-exposed post.
My best to ya and hope this helps.
Jay J -Moderator
PS: If I'm way off on my thoughts, maybe someone else knows what you're saying. At worst, come back with more 'details'. Sorry ...