HI Adam
i worked on mine a while ago, adjuster bolt goes through backplate, put a washer on first, both washers look similar size if so i would go for the galvanised/stainless looking one on outside as more durable.
on the inside of the back plate put other washer on bolt, then the spring seat over the bolt with recess upwards, the spring should now locate on seat, the snail cam should now fit on end of bolt it should locate on it perhaps with two flats on bolt/cam hole. the cam is retained by small bolt, its likely the spring will need compressing before cam engages on flats (tightening the samll bolt will pull it in but need to be aligned properly).
you can practice layout first before fitting
just remember once fitted do not overtighten the aduster nuts as this can strip the flats off the bolt, then cam just turns on shaft making adjustment impossible
