What you want would be cool, but the technology (the HDR) is a little dated for that.
And that in a nutshell is the answer.
I sold my HDR years ago, replaced by a DAW...so I don't remember what tempo or BPM control that thing had. But it does spit out MTC that the D8B needs to follow, and therein lies the "dated" quality of what is possible.
The D8b has a button labeled SMPTE View in the transport area (the software Locator has 2 radio buttons to mirror this). Click it to turn off the SMPTE View LED and the D8B merrily starts displaying bars, beats & ticks...based on the tempo you set in the D8Bs MIDI Setup page.
Problem is....it's
always 4/4 and it doesn't follow the tempo or meter via MTC. Unless you're doing a strict dance tune or something, where the tempo and meter never changes....this D8B function is pretty much useless. At best, it's a poorly implemented convenience.
Like Bruce suggests, print a click and don't bother switching the D8B's time display to BBT. As to generating a click, there are a ton of little audio devices that can do this like cheap small practice stomp boxes or drum machines...etc.