Is overhead/G&A and profit for the direct design labor hours included in the computation?
See FAR 15.404-4(c)(4)(i)(B) which states that "The contracting officer shall not negotiate a price or fee that exceeds the following statutory limitations, imposed by 10 U.S.C. 2306(d) and 41 U.S.C. 3905:
(B) For architect-engineer services for public works or utilities, the contract price or the estimated cost and fee for production and delivery of designs, plans, drawings, and specifications shall not exceed 6 percent of the estimated cost of construction of the public work or utility, excluding fees.
A contract "price" or "estimated cost and fee" (determined by which family of contract you use - Fixed Price vs. Cost Reimbursement), includes all cost elements including overheads, G&A, and profit or fee.
For specific questions about the pricing of your contract action, be sure to discuss with the cognizant contracting officer who will be determining the fairness and reasonableness of the action as well as your legal advisor if there are more complex concerns.