it doesn't really matter back vs belly that small.
I wanted to inquire about this .... I can't find anything that is a good price that doesn't use heat rope. I'm a flexwatt type of girl. Jerry, I see myself doing something like that but with plastic.
I could hold 24 6qt tubs on my plastic, or 16 15qt and 8 6qt. Its two plastic shelving units stacked together with 3" flexwatt. Cost me $40 for the plastic parts, around $50 for the flexwatt, tape, wiring, and $50 for the on/off thermostat (1000w). The tubs of course cost an additional cost, but I could buy this over time as I built my collection. So for about $250, it's full. Comparably, I feel better about buying a premade rack now pricewise, if it came with tubs and heat, but FLEXWATT. So I'll have to search around now!