Trans-Dapt motor mount experience?

Does anyone have experience with using Trans-Dapt motor mounts in their 72 A-body (or equivalent)? Not the mount bracket but the rubber biscuit portion.
Trans-dapt shows a #4219 that says it has a short interlocking and a tall interlocking mount. Basically the height of the mount is what is different. But why would you want two different heights? I've only ever seen the standard "short" flat biscuit used (like on my 71 Demon 340). This is for a 408 in a 72 Demon and not sure I have height for a taller mount. I want to use the interlocking type (it will also have a torque strap) so I figured if nothing else, I could use the short interlocking one on the driver side and a standard one on the pass side since that mount doesn't take so much abuse. But even after calling Trans-Dapt, I'm not 100% convinced they even make a short interlocking mount. So I thought I'd turn to the experts...thx!!