I thought you could roll the rear out and flip it up with the pump on top and change the gasket with the rear still full of fluid? Least that's how I think I've done it before.
Regardless, I'd pull the tunnel cover give it a bath and go in the house. When its clean and dry you should be able to find all the leaks and determine how many of them are worth the headache. By the way, now is a perfect time to address trunnion wear and check the condition of the driveshaft at each end.