My 93(207000 miles) starts hard in am as well.I too would like to have the answer you seek. When it warms up it will start fine rest of the day, it is the overnight cold engine which gives me fits about start up. I am suspect of lawnmower syndrome as fault.(Dirty valves stem body hanging up in valve guide).I run mobil 1 10 - 30 and my rpm cranking is fine in am. I read elswere to have psi checked in fuel system imperative to maitain psi at shutdown and hold pressure in system. check the fuel pressure regulator for leaks at vacum hose point.I have not done this as yet but intend to do so.
Mike