Let me preface my response with this: they say that when your only tool is a hammer, every problem is a nail.
The way I'd solve this is with ADTPro. A .hdv image is really just a straight ProDOS-order image (i.e. .po) and as such ADTPro would be able to send that and write it on top of your hard drive in place. If you could figure out how to attach it to a 68k Mac and have it write that image to it, that would likely be much, much faster. But I'm not sure how that would really work. The ADTPro solution, while slower, would let you leave the drive in place.