Spring verb DIY

Hi
I have a accutronics reverb tank I pulled from an old marshall
I want to be able to use this verb as outboard during mixing guitars reamping etc...

It has the standard RCA in and outs. So plugged the output of my converter into a api312 then the output of the micamp into the RCA on the reverb tank, then the output RCA on the tank I plugged into the input of another 312 and the output of that pre back into my A/D sent out a guitar track and it sounded really good.

So my question is, is this safe to do? can I fry anything? I don't know the impedance(s) of the reverb in an outs, but by looking at the transformers being slightly different sizes I assume their impedance are different?

Is this all problematic? It sounded really good and have more than enough gain on the inputs and ouputs. And the verb is very deep and clean and very cosmic quality to it that I have never heard using convolution or algorithmic springs plugins.

anyone ever wire up a tank for outboard use? Is there a preferred way to do this with after market devices? I really don't want to buy a DIY kit or anything since this seemed to work