You shouldn't need to plug the hole, other then to keep junk out.  If you have any oil in there it is from a leaking front main seal.

But yea, you get used to tearing into things.  My Tracker has been in the shop for a couple of months with transmission issues.

Any Leak leads to this anology,
It's just how a dripping fauset turns into a REMODELED BATHROOM!!
Oh, just pop a new o-ring in...........
Oh, Oh, after removing fauset, you see it's been leaking for longer than you thought, and the back of the vanity is rotted.....
Oh, Oh, Oh, you pulled the vanity out to see that all the dry wall is molded up...........
Oh, for the love of God, now it's the damn 2x4's have dry rot......
                                                              AND THE FLOOR is all punk'd up back there  TOO !!!!!!
                                                                   all the way behind the shower...........

Before it's "ALL IN" you have a REMODELED BATHROOM !!

MY 2 Bits,     CAPT

Any Leak leads to this anology,
It's just how a dripping fauset turns into a REMODELED BATHROOM!!
Oh, just pop a new o-ring in...........
Oh, Oh, after removing fauset, you see it's been leaking for longer than you thought, and the back of the vanity is rotted.....
Oh, Oh, Oh, you pulled the vanity out to see that all the dry wall is molded up...........
Oh, for the love of God, now it's the damn 2x4's have dry rot......
                                                              AND THE FLOOR is all punk'd up back there  TOO !!!!!!
                                                                   all the way behind the shower...........

Before it's "ALL IN" you have a REMODELED BATHROOM !!

MY 2 Bits,     CAPT

Been Threre, Done That (too) 

Just Letting you know,
You're NOT ALONE out there........
Life is CRUEL sometimes.......usually when you are a 1/4" from broke, and already down to Mac N Cheese & Spam Sandwiches!!

CAPT

Spam? someone say SPAM?

Yeah, "small job big" we call it out here.