97 Z71Auto to manual trans conversion

[Woody1962]

I’m getting ready to do a full manual conversion on a 97Z71 , 5.7,4L60E, np243 case. I’ve purchased a 97 Silverado 2500 2wd as a donor for engine, trans, dash, ECM and related wiring, steering column. I’ve also purchased a NP 241 and floor shifter with the correct input shaft for the planned nv4500 trans. My question is in installing the clutch master and the floor shifters. I see markings on both the firewall and floorboards. Are these knockouts or do they have to be cut out ? Also how hard a job is it to do the NV4500 4x4 conversion ? I’ve never had one apart but from watching videos it doesn’t appear to be too bad.