Shimless bucket conversion Options

[playr158]

Ok so in all my reading over on Mr2oc i've seen alot of setups and looked at a ton of different situations and options on ways to build things.

but one thing i've been confused about slightly is the shimless bucket conversion
i know where it happens but i don't know why and how it happens?
if someone could explain the benefits of the conversion and how its done that would be great

[playr158]

By removing the shims it's supposed to be more reliable at higher revs.

Clearance measurements between the cam lobe and bucket are taken at each valve.
The thickness of each shim and bucket is measured.

With this information you can now order the correct shimless bucket for each vavle by comparing the total thickness of the original shims and buckets and comparing it to the clearance measurements of each cam lobe and bucket.

so now is the bucket supposed to touch the lobe at all times and the goal to get the right thickness to achieve this?

or is there a specified "clearance" which we would subtract from the actually distance to get the size of shimless bucket needed?