Abstract: A subsea wellhead assembly has a tubing hanger landed in a wellhead housing. A spool lands on the wellhead housing and has a bore with a laterally extending production flow outlet. A tree cap having an axially extending flow passage and a laterally extending production flow outlet lands within the bore of the spool. Upper and lower seals on the tree cap seal between the tree cap and the bore of the spool above and below the production flow outlet of the spool. An isolation tube on a lower end of the tree cap sealingly engages the production flow passage of the tubing hanger. The tree cap may be ran with the spool as an assembly and retrieved from the spool for workover operations.