Welcome.
Those posts you refer to reddit and sysdfree are outdated now, because boot-66serv has really become boot@ -66serv and is a module service. See the obarun wiki on modules and boot module in specific.
I know of bedrock but haven't tried it, with void I am a bit more familiar.
The basic configuration different between obarun and void in terms of services is where they are placed, /usr/lib/66 in obarun /usr/share/66 in void. With boot, as I found out, if you just copy obarun's to /usr/share/66/service it fails because within it there is a use of the script module.sh which is directed to /usr/lib instead of /usr/share, otherwise it is identical with what void's teldra has created.
https://github.com/teldra/void-packages/tree/66-boot/srcpkgs/boot-66serv
You can build it into an xbps package or just copy the stuff from the git to the appropriate locations. I've used it for glibc and musl. It works great. Read the contents of the 66 script and try to understand what it does. This is teldra's solution so you don't have to remove anything runit related from void and it would be easy to switch back. Basically it moved the runit powerfunctions out of the way and makes room for the s6 functionality and you can revert if you didn't like s6/66. Basically he is trying to make it into a compatible pkg within void, so there would be no conflicts.
https://github.com/mobinmob/void-66-services
The 2nd link is by mobinmob
and has services that work on void without modification, they are a bit simplified compared to Obarun's to blend better with runit simplicity.
The configuration of the boot@ module is just the same as in the Obarun wiki, but if you have the old boot-66serv (non-module) make sure to remove it before using this. Also tty@ -66serv is required because on the new module tty12 becomes tty@ tty12 using that script, while the rest of the tty is defined within the module as tty-rc@ tty*** and in the module script you can define between 0 and 11 ttys.
Monbinmob is the void expert and I have to admit I have avoided void lately, after getting 66 to work, just the presence of elogind in the repository and its link to a whole load of crap averts me :) But I don't use consolekit either, so it doesn't change anything from me, just the feelings from void were hurt.
I do admit to using xbps on arch and pacman to void with a few things I can control their dependency conflicts, or little script packages, but there are strict religious people who scream "policy" to me about such things, so I'll be quiet.