Use a cover letter and state the limitations of your analysis. Do not use the term "certify". I suggest something like:

I have reviewed the geometric properties of the sections used. The geometric properties meet or exceed the properties of the sections originally proposed.

Agree with Ron. In the US an engineer’s stamp and signature only identifies the engineer who was directly responsible for the indicated scope of design. It does not certify, warrant, or guarantee anything.

There is an implied certification there, but only in that the Owner or other who will be depending on the plans is assured that a licensed engineer did the design.

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At least in some states, a cover letter may or may not be sufficient. If it is bound into the report as the first sheet, perhaps. For example, here are the rules in two states where I practice. Neither one specifically allows a cover letter to be stamped and not the actual report:

"Either the cover, title, index, or table of contents page, or first sheet of any report, specification, or other professional document prepared by a registrant or the registrant’s bona fide employee"

"If civil engineering specifications, calculations, and reports are required to be
signed and sealed or stamped and have multiple pages, the signature, seal or stamp, and date of
signing and sealing or stamping shall appear at a minimum on the title sheet, cover sheet, or
signature sheet."

Ontario Building Code requires review of construction stamped project completion notices to be filed with the building department. Essentially this is the cover letter to the as-built report that states in our opinion we think they built it right with qualifying statements. The report itself is just a collection of information provided and is not stamped, as there is no opinion provided or engineering calculations.

Appendix 6
http://www.peo.on.ca/index.php/ci_id/22090/la_id/1...

Quote (malikasal)

knowing that the project is not in the US but the client is american and he is asking for a PE to STAMP the Report.

Based on this statement, I'm assuming there's no actual law or jurisdiction requiring the stamp aside from your client's requirement. As such, I would infer that it is completely up to your client what they will accept. Your approach seems reasonable to me given what you've stated. You could either submit it to your client and see if you get any comments or response on the subject or inquire to them ahead of time if such a statement meets their expectations/requirements if not clearly defined.

thank you guys for the input!

ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

Another thought, your stamp is for the jurisdiction you practice in, if you are working in other jurisdictions you are not licensed to practice your professional liability insurance may not cover the work.