Blowing main 80amp fuse in MX5

[Wallers]

Long story short, I disconnected the battery to put it in another car. Fannied around and then attempted to connect it up again on the original car, positive first then negative. Whilst connecting the negative it sparks a bit and blows the main 80 amp fuse. So I take the 80 amp fuse out of my car, put it in the other car with the battery disconnected, reconnect the battery being super careful and again I blow the fuse. So clearly I have a short, how I gain this short when it appeared to be fine before I don't know.

So I've managed to take two cars off the road as I don't seem to be able to find anywhere in Coventry that sells PAL type fuses

[Wallers]

If anyone is interested, I'm basically an idiot.

[Si]

Yes, yes you are.
A '-' looks a lot like a '+', doesn't it? Twice.

[Wallers]

Shh. As the article on Piston Heads states the terminals aren't colour coded and I'm an idiot.

[dow]

Haw Haw! Can we poke you with sticks for a while then?