I've messed around with using bazooka style screens in a keg mash tun but it really doesn't work if you're going to put a flame under it. Manifolds and such tend to trap the grain tight to the bottom of the keg and it gets burnt. A full false bottom (15" disc) is really the way to go. You can buy one from me or somewhere else, either way.
Can I send you some pics of what I have here? 3 keggles and I'm missing some small parts to get them functioning and I not quite sure where to start. I want to end up with a 3 keggle single tier operated with pumps.