Is the jumper between the radio and tuner supposed to be over a certain length?

Doesn't really matter.   Should be a workable and convenient length for your setup.

Just use some of the same coaxial stuff you're feeding your antenna with (I assume its the 52 ohm version common to most HF gear).   I use rg58 to the tuners I have and 450 window line to the ant's themselves.  

You are aware that you don't need that tuner if your antenna is resonant don't you?  

Quoted: Doesn't really matter.   Should be a workable and convenient length for your setup. Just use some of the same coaxial stuff you're feeding your antenna with (I assume its the 52 ohm version common to most HF gear).   I use rg58 to the tuners I have and 450 window line to the ant's themselves.   You are aware that you don't need that tuner if your antenna is resonant don't you?

Yup, I am aware of not needing a tuner for a resonant antenna.  But the antennas I am using run from 2-30MHz. So I will definitely need a tuner.

--Scott

While you can have issues with certain lengths of coax, it is unlikely that you will induce any problems by using a typical 6" or so long jumper cable.

FWIW, my new tuner should arrive today.  woot

I made up some coax jumpers about 12" - 18" long for this purpose, length shouldn't matter.  It would take a pretty long jumper to approach an "active" length on HF frequencies in any event.

As an aside, the best jumper coax I have ever used is Times-Microwave LMR240 ultraflex.  It uses a rubbery material for the outer jacket and stranded center conductor so is very flexible. It also has the 100% foil shielding which helps with stray RF in the shack (very important for repeater applications).  LMR240 is RG8X size.