I actually used an old hydraulic roller lifter set and retainer, then shaped my dowel to fit the lifter center on my bench grinder. You won’t be pumping up your lifter anyway. You’re only measuring cam lobe lift/duration so the length of the dowel Doesn’t really matter as long as you can set up your dial indicator to move smoothly and be repeatable through the range. You only need the dowel to be long enough to be able to maintain a straight line from your lifter to your dial indicator. This way it’s fairly easy to set up.
There are lots of YouTube vids out there to help too.
I used my original pushrods on final assembly.
This is a great read
http://www.hughesengines.com/Upload/productInstructions/camshaft_instructions_Aug_2019.pdf
Hope this helps.