I have sourced a backbox for £cheap for my MX-5.
Don't get excited, its not a mod as such, its the standard backbox off a similar car which has done about 10k. Mine has done quite a lot more than that and makes funny rattling sounds at idle and at 3500rpm.
Anyway. Has anyone got any tips or covenants? The resonance at 3500rpm is kind of cool, but the one at idle is sporadic and pretty embarassing.
The bolts holding the centre section to the backbox on my car appear to be in quite good nick, possibly stainless. However the nuts are not in good condition and made themselves out to be the consistency of oatcakes when a spanner was wafted in their direction.
Tell me I need an angry grinder. (c: