I am wanting to switch the feed from the bottom to the top of the rad. Obviously I will need to switch the bottom and top bushes around. Here is my dilemma are they LH or RH threads. I have tried to undo in both directions and cannot shift it. The bushes are at the opposite end from the bleed valve and at the end where the bottom contains the deflection baffle. Have spoken to Zehnder who do not appear to know! Is a tad odd as they make them. Anybody know?