The Beseler 23CIII is mostly the same as the later versions of the 23CII, likewise for the longer column XL versions. I measured my 23CIIXL equipped with the Dual Dichro-S dichroic color head.
The baseboard is 30 mm thick. The top of the column to the top surface of the baseboard is 1040 mm.
With the lamphouse against the upper stops, the distance from the top of the lamphouse to the top of the baseboard is 1479 mm. Thus, the overall height including the thickness of the baseboard is 1509 mm.
In that position, the top of the negative stage to the top of the baseboard is 1078 mm.
Most paper easels are about 1” or 25 mm tall. With an easel in use, the maximum negative-to-image distance is about 1053 mm.
Depending on the dimensions of the lamphouse your machine has, it might have somewhat different dimensions as referenced from the top of the lamphouse.
Here’s the 23CIIIXL manual. It gives the dimensions on page 1. Magnifications and maximum print size with various formats and lenses are given on page 3.
https://125px.com/docs/manuals/darkroom/beseler/beseler_23ciiixl_manual.pdf