the genuine zeemax kit is designed, and finished to perfection, so that it can be bolted together and finishes flush with the bodywork, the whole idea being that you DONT use filler on the jointing faces or blend it to the bodywork in any way whatsoever. The side skirts are bonded with sicoflex at the top and screw fixed at the bottom and everything else bolts into place - no gaps.
the copy kits are way thinner than the original and flex easily, certain areas of my kit are in excess of 10mm thick which is what gives it strength.
sorry to say, but if its a copy kit, and thin wall, it will flex and crack everywhere you have used filler.
Zeemax dont fit kits - they have bodyshops they recommend who all fit to a very exacting standard, thats one of the reasons its so expensive, and why i guess its tempting to get a cheap copy and fit yourself.
where you are at now, the only real fix is to dig out all the filler and use resin where you can, but I think this will eventually also crack, spider fracture and not look to good.
I learned the hard way and ended up binning a kit to start from scratch, or more to the point i let the recommended pro's do it.
The recommendation above of extra steel bracketry to support and brace is a good idea also - anything to eliminate flexing.
Edited by roofless, 25 December 2008 - 07:05 PM.