You might try the position calculator at stewmac.com to determine correct location for the III / IV / V marks:
http://www.stewmac.com/FretCalculator/
Rig it for 24 'frets' (or 36 for a Peanut) and 34" (or whatever) nominal scale length, and you'll get the distance
from the nut to the hypothetical 3rd, 5th, 7th, 9th, etc. 'frets'. You'll see the first octave on a 34" scale is exactly at 17", second octave at 25.5" (half-the-distance-to-the-goal-line = 17" + 8.5") , and so on. The real tweek classical purists would use different mathematical temperings, but hey, this is fretless bass we're talking about.
If indeed Wish's marks are way off from what you're currently using as scale, consider forgetting about a preconceived scale length and rescaling it to 'reality' by placing the bridge at 2x Wish's nut-to-octave-nailhead distance, and see if the rest of his markers suddenly come in to tune. From what I remember by reading some of his eBay ads, almost all of his basses are 34", and he doesn't have the proper measurements for certain less-common scalings when somebody asks for 35" or 37", etc to solve B-string buzz. I'm betting he uses a pre-marked template to lay out his nailheads.
Forget about the bridge-to-string-holes distance - something tells me that this may be less-than-consistent across various Wishes. Worry only about nut-to-bridge, and let us know how it goes!
Pete
(who learned about floating bridges the hard way back in my banjo days)