mx5/miata suspension knock

[staticmx5]

Hey guys I was hoping someone could help me out. I've got a 1994 clubman and after I put my suspension in I've got a knock from the left hand rear. I installed brand new stance coilovers and I have them as low as they will go, but its only on one side that is knocking. I though it might be the pillow top on the strut but ive stripped and inspected it and I couldn't find any thing wrong. I've also disconnected the sway bar as I thought it may be knocking on something but the noise is still there.

Ive checked the obvious, and all bolts are tight, but I cant seem to find the knock. The bushes seem fine with no excessive play. So basically after a thorough Google search I'm stumped! Any help or ideas you guys may have would be greatly appreciated. Thanks

Max