If you mean Dragon kit 6814, then I believe it is common wisdom that this is a "paper panzer". It is based on the 324/3 with the normal L/24 gun replaced with an L/48, presumably the KwK 40. I imagine the mounting would have struggled with the recoil force of the more powerful gun, especially without a muzzle brake: the PaK 40 mounting in the 234/4 for essentially the same gun was more substantial. BTW, there was no L/46 7.5cm gun: L/43 or L/48.
Only 88 of the 234/3 were built anyway, followed by 89 of the 234/4. The role of the 234/3 was essentialy fire support, although the shaped-charge round for the L/24 was reasonably effective against AFV's (better than the 5cm AP in the 234/2). That changed to a principally anti-tank role with the 234/4, which was essentially a wheeled panzerjager.
So I can see the attraction of substituting the L/48 gun to quickly re-work 234/3 into a virtual 234/4. If this could be done on the 234/3 then it could also theoretically be done on the 250/8 and 251/9. But as I said, I don't believe it ever happened: possibly a one-off experiment, but no more.