Manual Control of Z Axis

Hello folks.
My first post here so first off, hope this is posted in the right part of the forum.
I'm reaching out for help here due to my limited knowledge of all things cnc, hoping somebody here might be able to point me in the direction of components that might help.
I'm a carpenter and joiner and recently built myself a small router sled for flattening slabs, constructed from 20mm slot 6 profile and using a Mafell FM1000 milling motor. I mount the motor in an old plunge base with a 43mm collar and it works great. Nothing cnc level but ideal for what I'm using it for.

Having done a few slabs now, the plunge router base is proving a tad annoying sometimes. With no micro adjust and depth stops at too large increments for surfacing bits, I have to lower my eyeline to view the workpiece and bit, then try and plunge and tighten whilst crouched below the router. This often takes me 3 or so attempts for each pass. It works but not ideal.

I'm thinking a small linear actuator rather than the plunge base would be ideal. This is where I need your help. Although you can buy these ready to go, motor and all for the z axis, I'm struggling for info on a more manual means of motor control. At it's most basic, what I'd be after is simple, manual up/down motor control - an up button and a down button. Is this a possibility with the stepper motors that come with the actuator kits and could you help me with what I need to make this possible?

Look forward to any suggestions.
Thanks
Stew