Regarding leaks,once water gets in it can run along wiring and scuttle bar and not come out directly below the entry point. Mine was coming in through loose window washer jets. They may look ok but if you can wobble them around then they need to be sealed & tightened. Dashboard off, remove washer water pipes and use a small box spanner to tighten. Fiddly! and then there's getting the pipes back on; I dumped the original plastic clamps and used small cable ties.
See also today's post from Roadsterboy regarding brass bonnet hinge and use of crack sealer.