delfield pizza prep table not reaching correct temp R12

[romanowski72]

Hi guys I need your wisdom!
I have a three door delfield prep table, and I cant get the top rail to temp, when I checked on it this morning the evap coils were icing up and temp of box was 46(this table is in my shop).
SPECS
r12 refrigrant no air in system its spot on.
it has a canister, the filter dryer and sight glass are mounted in a vertical position so with that combo I would think I would have bubbles which I do. Is that normal i have not seen a dryer that was not horizontal?
ambient was 88F
discharge was 149f
subcooling 111f or 38degrees
high side pressure was 180-185psig this did drop to around 160psig when the table hit 38f
If I remember correct my desuperheat was 21f which should be good.
Suction pressure is 30psig.
system has dual evaps with txvs one of my txvs was mounted in 12 oclock so I switched it to 9 the other was mounted vertical so i moved that down and over to 3 oclock .
Unit is missing evap covers so I have thin cardboard over evaps to help with airflow. could cardboard be insulating a little bit?
I am stumped, and i think the cutout might be bad also because it should have shut down after running all night, its set at 15 and suction line was 12 before I went to bed. it rose during the night as did the box temp.
This unit is a bloody wreck, the customer dropped it off, and it was missing evap covers, a evap fan was missing, all the electrical was torn out. The customer says he has the covers for evaporators.
I am not sure where to look next? I know this is a long thread but any advice would be greatly appreciated from some of you more experienced.

[mikeref]

Set what at 15? Thermostat at 15 F or pressure switch at 15 PSI.
Best get the proper evaporator covers because if your customer doesn't have them....