This is up to you because it is an untested modification, but since they are apparently designed to fill with water and hold it inside indefinitely, I blew out the loose rust and drilled a series of small drain holes in mine. Painted the drilled holes, of course, and treated inside with rust catalyzing primer and 3M Rustfighter I. Time will tell how that works, and I'd have tried the Eastwood product if I'd known about it. However, I've had good results on other vehicles by my method before.
In God we trust.
All others bring data.
'02 Sport, soft top, 6 cylinder
5 speed manual, 4" lift, 33.5" tires