to avoid taking off the cover you could change oil as the dealers do-from above.do a search on 'topsider' or 'oil suction' and you'll get more info than you need.
'95 s500 (bought for wife but can't bear to share!!!) 125kms
'92 legend 180kms
'88 tbirdturbo(fantastic car-only regular maint.)120kms
'87 mustang gt(gone)
'85 mustang gt(gone-but not forgotten)