If you use a jig without a base, and you have an anvil, that should work fine(ofc you will not break the anvil)
This was my case, and luckily I was able to use it without too much hassle securing the washer with some tape on the base.
A CNC-cut aluminum base is cool anyway: can you share a few pictures?
I do agree: that it's overkill, but it might be fun to use it!
With the anvil and the tape, the results should be good enough imho.
This is the Jig with the CNC base:

This is the whole jig:

I have photos of the regular jig at the web, and the product manual shows how to use it:
https://hideyourkeys.io/product/stamping-jigs-manual/Suggestions are always welcome
P.S: I reuploaded the pics of my other post, check the M6 variant as well, I think that one is a very interesting solution
In today's digital age, using them has become rare. They don't want to use it alone, but those who use it have been doing it since ancient times. and currently. They are able to beat the digital ones because they are all hand made and very secure, and also I like the post that Filipino bro is doing because he explains it so well and I'm actually surprised to see it today I'm actually surprised even though I'm new. But I am inspired by these.
Anyway brother, thank you for explaining us so beautifully, we could learn so many beautiful things thanks to you.