Labs seem unreliable to construct (8)
I believe the answer is:
assemble
'construct' is the definition.
(thesaurus)
'labs seem unreliable' is the wordplay.
'unreliable' indicates an anagram.
'labs'+'seem'='labsseem'
'labsseem' is an anagram of 'ASSEMBLE'.
'to' is the link.
(Other definitions for assemble that I've seen before include "Put together all the components" , "Manufacture" , "fit together" , "Come or bring group together" , "Gather together in one place" .)