The scrwes will be all the same, philips, we are working on this issue.
There will be also hop up option for titanium screws and aluminium shims.

In the pivor area there are preaty high forces and I dont think another piece will stay togheter with the rest. later I will show you our ideea for 3 different caster options and lot of camber options.

And yes, you can use left upper arm for left and right