Question on Option Usage

Good day--

I am preparing a service contract for a one-time relocation of equipment from one facility to another. This contract will include design/layout services, install, testing, etc... I intend to create ONE FFP contract line item (CLIN) on this contract to accomplish the work in accordance with the SOW. We want an option item for engineering support services (10 hours at FFP fully-burdened hourly rate) that may be used during the later stages, should we require such. (NOTE: We want this to be an option, not a T&M (IQ) CLIN).

So, my question surrounds the option clause. I will include 52.217-5?Evaluation of Options (not exercising at time of award)--not an issue. But, I don't think 52.217-7- Option for Increased Quantity is appropriate-- because my option CLIN/and service is different than the basic CLIN

And..52.217-8-Option to Extend Services, extends the term of the contract. If we exercise option labor hours....it may extend the term, may not. Would this be appropriate to use?

I will appreciate all advice.

WAIT!! I had another idea I would like your feedback on: maybe I should include up to XXX hours of this engineering support in the FFP portion and not worry about any options. Your advice is sought...PROS/CONS