93 bird 3.8L oil pump replacement issues

My oil pressure drops to almost zero and the check engine light comes on after driving about 10-15 miles. Its fine when i first start it up but once the engine warms up is when i get the dreaded light. but only at idle and when in drive not when in park or neutral. After a few minutes you can hear a small but noticeable knock. Im pretty sure its the oil pump. But different poeple have told me conflicting things about removal. one guy told me I have to drop the pan and raise the engine to get to it. another told me its behind the oil filter. and the last guy told me id have to pull the timing cover to get to it. which one is right. also is there any tips anyone can give that would maybe save me a little headache before i dive in. thanks

Get youself a factory shop manual here: http://shop.ebay.com/?_from=R40&_trksid=p3907.m38.l1313&_nkw=1993+Thunderbird+shop+manual&_sacat=See-All-Categories

Your engine probably has a lot of miles on it and the bearings are wearing out. When the engine warms up the clearances open up thus reducing the oil pressure. A high volume pump will help but it isn't a cure all for a high mileage engine. Use a good quality oil and a Motorcraft oil filter.