full manifold vacuum advance help

[m.lander]

I have a accell 59107 hei distributor and want to switch to full manifold advance. i understand changes have to be made to do successfully make the change such as to screw the adjustable can in or out. the manual that came with the distributor says if you rotate the screw counter clockwise till it bottoms out then turn the screw 4 full rotations clockwise it will give you 7" dist. +- at 12" vacuum +-. with this being said how many full turns clockwise would i roughly want to turn the adjustment screw to run full manifold vacuum. also, what other changes would need to be made. i know this has been discussed a lot and trust me i have been reading on this subject for months and i cannot grasp the concept. thanks for any help in a less confusing way. all of my attempts have resulted in poor idle and just general failure to make the change.