MK1 splines are never an inch. They take a 17mm nut IIRC and 15mm sounds right. NA and NB Mazdas are the same, dont know about NC.

http://www.demon-tweeks.co.uk/perfor...wheel-boss-kit

Same boss for 90-05 cars.

Sounds to me like your boss is wrong.

Cheers
Stot

Thanks Stot - that is exactly what I thought, I have been back to the seller of the boss who is insistent on it came off a 1.8 MX5. Looks like I will have to buy another.

Sorry guys, its been a long time since an update and as some of the (non) progress has been detailed elsewhere I'll do a summary. (Sorry its a bit long).

The engine and gearbox were in, steering and suspension sorted, radiator mounted and I've sorted out all the plumbing so I tried to sort out the wiring. The MX5 I broke up was working when I stripped it so I thought all was well with the wiring but just to make sure I laid it all on the car and hooked it all up to test it out with the original loom. I had previously removed wiring for electric windows, air con, things that were not connected and tidied the loom up a bit.

I hooked it up and although the speedo lit up with its mileage and the engine turned over the batt light didn't come on. I spent ages looking for wiring diagrams for my Mk 2 but could never get an exact match so testing voltages was difficult. Eventually I found water damage to the plugs on the ECU. I bought some from a guy on facebook and after waiting ages they didn't arrive. I found some more at MX5 city, they didn't arrive so after talking to them, apologies, they had forgotten to send them. A set arrived, the wrong ones, for a Mk1. More apologies and eventually another correct set arrived. I replaced the ECU plugs but no change. I found a very useful sheet which give all the expected voltages and what they connect to for the ECU but couldn't get them to match correctly. I checked inside the ECU and lots of corrosion, wires missing and lots of green corrosion. Now I replaced the ECU, immobiliser computer and the transponder key set and steering lock.
Eventually I got it hooked up and it turned on with proper dash lights. I hadn't got the fuel sorted so a delay.
I fitted the loom properly with clips every 200mm or so, ditto the fuel system, made a battery tray and put it all together properly.
Final connection of fuel pipe made today at about 3pm. Hooked up the FP to ground contacts on the diagnostic socket and the fuel pump worked, put some fuel in stolen from the lawn mower and let it prime.
Turned the key and IT STARTED!!!!!!!!
Never thought it would after all the time spent getting nowhere and I don't understand why it ran before being dismantled but Hoorah, its finally coming together after 8 weeks messing with the wiring!

Bloody hell well done for persevering! :)

Sorry guys, this has really been too long but now is time for an update. I lost the will to pursue the car over winter, there is not much room in my garage so I started again with the weather improving. LOTS of jobs have been done with loads of problems solved but the car is now finally built and today I sent off my IVA application together with cheque for £450!
I have hundreds of photos to update my blog and will update it - eventually- so apologies for not doing. This blog has been brilliant though, I have a problem, search for a solution, and there it is! If its not there it always has been on the Locost blog which is why I haven't done very many posts. Promise to keep you all updated over IVA though :-)

Well done for pulling back into the build and glad your to this point, I didn't say finished cos they never are lol
Good luck with the iva hope you don't have long to wait

This morning at Norwich at first attempt - IVA PASSED!
Dennis the tester was excellent, he pointed out a couple of things that I was able to quickly rectify, a little bit of edge trim, a brake pipe rubbing on full lock and a tether for my filler cap. Hadn't been able to check the speedo but that was 2 mph high throughout the range, emissions well inside the limit, brakes test ok and only 94db on noise. Now for battle with the DVLA and get it on the road for - er - November?

Congrats Ian well done

On another note, the ecu plugs for the mk1 incorrectly sent to you, have you still got them? I need a set and am struggling:mad:

Hmm - not sure Chris - I'll have to have a rummage in the garage, I'll let you know

Congratulations on a first time pass