Strongly recommend you buy the spars from Kitfox. Aluminium suppliers here in Australia only supply in 12 ft lengths and if your KF5 has the same wing as the KF7 then suppliers other than Kitfox won't get you the length you need. I know this because I had an "incident" on my KF7 wing build and ordered locally - Kaiser manufactured in the USA. I had to design an extension to the outer section for an extra 18". Also, as already suggested by Jim Chuk, a heat gun will soften Hysol if that's what was used. Any other adhesive used in the original build - don't know.