i would say looking at those pics that they used a really big glass bead. i can get my stuff pretty close to factory finish. only issue is getting them too bright on rough cast surfaces can make stuff look like cheap aluminum spray paint has been used.
my business is media blasting. one part of it is vapor blasting. i have done tons of carbs and they turn out really well. only issue is keeping the media out of the orfices and out of the throttle shaft springs. i normally ultrasonic before and then vapor then ultrasonic again and blow out...
BPE TorqueFlite Kickdown Cable Kit - Bouchillon Performance Engineering money well spent get a correct original throttle cable bracket and start there.
silver step up spring those are the stiffest. start there
8" of vacuum is a problem with that carb. (at 8" i assume its a MP cam)
600 eddy will not work with more than [email protected] duration
check for a intake/carb gasket leak too