Robin i fitted some mods to my wedge to make it smoother in operation , you might be able to rig something yourself but theres a kit available to replace the Altizmuth controls
http://www.optcorp.com/product.aspx?pid=3111 , this cuts a lot of the backlash and is certainly a big improvement , there is a bigger kit that replaces the altitude gear as well and better machined crossbars
http://home.cfl.rr.com/mitty/Combo_SLO-MO_Kit.htm
I used a thin cutting board and routered out holes to match the spacing for the bolts that hold the wedge to the tripod and their movement , it works very well and acts as a shelf for stuff as well