as above. you really should get it checked by someone who has experience.

my advise is dont buy recon metering unit. buy a good tested checked unit secondhand. Dont just buy any random one tho. Find someone doing a conversion whos unit has been working with printouts etc of co%

they are out there as I take them off constantly. however I guess only 1-2 out of 10 would be good enough to warrant buying. Not that im selling!