On the jb3 however I am getting no levels and on the UA-5 the peak light isnt coming on and I am playing with the knob on the back next to the rca ins to see what may happen and I am still getting nothing.
OK, I hope my memory is working here. My first use of the UA-5 was nearly identical to yours.
Make sure you set your JB3 to optical input. I assume you will also set to WAV, which will not have any options as you can only record at 16 bit 44.1. this will effectively render your JB3 as a bit bucket and the UA5 as the processor. You will not need to set any levels on the JB3.
My AT 853's were modded, but as I recall when I used them with the UA-5, I went through the RCA's on the back and used a Battery Box and did not use phantom power. It is a little awkward though, because you have to set the levels using the small knob on the back, the ones next to the XLR jacks weill not work with this set up.
For me, this is why I eventually invested in another set of mics (AT3035) that had XLR jacks and for which I could use Phantom power.
That said, the time I did use the AT 853's, I did get a fantastic recording. It ran a little hot (again hard to reach the levels with the UA-5 in a bag), but the sound was clear and crisp.
Have fun!