Removing the inners doesn't prevent cam failures if you screw everything else up.

Motor has to be clean, clean, clean; lifters free in their bores; no guide to retainer(seal to retainer) interference - proper clearance at max lift; no coil bind at max lift; all internals pre-lubed; correct break in oil and/or additive package; spin distributor out of engine to make sure you have spark at the plugs; carb bowls full; get oil pressure; install intermediate shaft then install distributor and verify timing is dead on using rotor and #1 tower in distributor aligned properly and reluctor to pickup coil aligned ( or points set ); engine full of coolant; fans in front of engine; light the engine and get up to speed and break in -