----wire it the same.
----assuming you already have a stereo system, then for many reasons just keep using that for mono. you already have a good quality (the best you have been able to assemble) signal path. if you try to throw together a completely separate mono system with less quality then your mono efforts will start out at a lower level. you will not really know how good it can be. stereo sums the two mono channels of music into a center mono image. in theory a single speaker does have advantages but in reality that is not a good direction.
---agree with others, don’t over-think it, use the mono switch on your preamp to start with to see how you like it.
---next find mono recordings where the recording is engineered to sound properly in mono.
---and for mono vinyl pressings try to find a mono cartridge. it has technical advantages over a stereo cartridge on mono records, and will have less noise and greater dynamics.