stroker crank case machining

[00.400ex#55]

for the stroker cranks above 4mm, the case needs to be machined. what exactly has to be done?? is it somthing that a local machine shop could do prety easily or will i have to send the cases to an engine builder. if anyone has any pics that would be awsome.

[GOTFEAR]

you can do it put the crank in and piston on rod with out the rings and put the cylinder on to so you need to rotate the crank and every were it hits you need to grind this area out little by little you need at least around a .100 clearance