Cleaning the oil pick up without dropping the pan?

Lots of great suggestions...I would drain the current oil that is in the motor and change the filter with a cheap one. Pour a gallon of cheap ATF in it and a quart of cheap 5w30 in as well. Run for about half hour, maybe drive around the neighborhood a few times. Drain it, change filter and fill with gallon of 5w30 and quart of ATF. Run it for hour or two, driving around, not beating it or running it hard. Change oil and filter again with whatever oil and filter you like best.
I did that to my Ramcharger when I got it 4 years ago. It was sludged up pretty badly, and still runs like a champ 35,000 miles later.