MF TEA 20 Air Filter Problem, Tyres

The housing for the mesh in the air filter unit is fairly badly dented in, so I cannot pull it down and out to clean it, it is filthy(hence using the other filter).I want to pull out the dent but can not with pliers etc. I was thinking of drilling a small hole then putting in a screw then puling out the screw to pull the dent.BUT, then I have hole(s) in the housing!I can not use a welder to tack a bit of weld on and pull it out either.I can not seem to pull the mesh out from the top either.Does anyone know the normal procedure for removing the mesh?
Also, one of the rear valve stems on the tyres is leaking from both inside and out,I presume the stem has corroded?I used a rubber sealer to try and stop the leak(very slow) but would rather a more permanent measure.Removing a Tractor tyre tube and repplacing it is(too expensive for me) and a bit above my experience,I thought solder but then the heat may melt the tube?It also has water ballest in both tyres.We replaced the valve but it still leaks through the inside of stem.I really can not remove the tyre, no time spare money or experience on large tyres like a tractor so a quick fix is my only option at the moment.Any help or ideas appreciated.

Matthew Nowell

Any ideas Appreciated.