In order to drop the pan, you will have to also disassemble the steering
bellcrank from its pivot shaft then slide it aside.  I don't recall but
you might also have to drop one tie rod.

After dropping the pan and removing the oil pump and rear main bearing
cap, use a large screw driver to start the seal in the engine block
moving.  You can usually "coax" it all the way around once started by
using a sharp object or needle nose vise grips to move the exposed
portion further.  Once it makes a 180° it will drop out.  

Put a thin film of lubricant on the mating (to engine block) surfaces of
the new seal half and it show go in without a lot of hassle.



More'n likely it's the pan gasket causing problems; but if'n you have
the starter out you may want to consider pulling the rear block drain
plugs and the Welch plugs.  Clean out the coolant cavities best you can
with some wire, then put brass expandable core plugs back, along with
stainless drain plugs.  
Getting an old main seal out can really be a bear, may almost have to
dissolve the rubber to get it out if it is really stubborn.  Be sure
everything underneath is spic and span before reassembling the pan,
don't want any dirt in the pan or on the new gaskets.  The new front and
rear pan gaskets, that thick rubberoid (or cork) is a bear to get in
place properly.  Not for the faint of heart.  
And it wouldn't hurt to pop a main or big end bearing to see how they
are doing.
And of course there is the front main seal and the timing cover
gasket.....................
Shouldn't take more'n 3 weeks.

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It can sometimes be tough to do it in the car.  Even when you loosen
all the main bearing bolts, the transmission keeps the crankshaft from
dropping down very far.  Be very careful how you pry and with what. It
is easy to slip and scratch the crank.  Try to use brass or aluminumn
tools, even if you have to make them yourself.  KK