Hi Kon,
I use one of these successfully on a number of mounts (Meade LX90, Celestron CG5, SW AZEQ6 & now on a Berlebach & Ioptron CEM25).
I level my tripod prior to fitting the head... simply place it on top & rotate it around to check various axis...
https://www.bunnings.com.au/stanley-...level_p5660362
Also comes in handy with home handyman projects where a small spirit level is needed...
Cheers