my 408 build

Yeah full car I could be wrong maybe it's not that heavy but I weigh in @ 300 so thats alot of it.
When its time for RHS heads I'm talking to brian.
What do I need for a harmonic balancer?
Is there anything I should be prepared for that I may need?
I just ordered my subframe connectors from seymour scamp.
Boy the headers are a tight huh? I'm going to make sure I have a damn good starter in it dont need to pulling that on a regular basis.
This is my first Mopar build I have been playing with chevy's for the last 20 years.