zero z mongrel

after many years of battling with torsional deflection in my x axis i swapped out the c beam profile for something more substantial.
slightly reduced amount of z but i very rarely need more than 40 - 50mm.
whilst in bits i figured id add ball screws to the y, not sure if going outboard will cause issue and im thinking about how to add some kind of covers for them, maybe brush strips..
all new plates are made from 12mm phenolic , i hope they last.
proximity switches all round.
next on the list is making a new z axis and sorting out the rats nest of cabling.