asking advices One of a kind TAPE magentic recorder repurpose Project

hello all,
this is super early stage but i have a very uncommon project at the table.
my dream reforder and the last one if ever i will get is a nagra sn. While droolimg over it i stumbled over a military data recorder that i got cheap.
iam fascinated by the heavy duty construction and build. Basicaly this is a loop recorder wich i assume records at 3¾ ips and on 1/4 track tape. But its possible its rather between 3¾ ips and 7½ ip.
the heads are Nortronics. First would be erase followed by rec and play (i think so).
i am unsure if data heads are different from audio but i dont think so, its magnetics after all.
degradation through the signal flow is another story (bias).

so obviously my startpoint is powering. I assume it runs on 24V DC but its a wild guess really.
how would you start with powering the thing?
next will be finding out signal flow and pins on the connector.
iam not sure if i should skip the board for audio and direct wire to the heads and build external impedance matching and amplification around it or if i should follow the signal flow.
reason is, its probably made for data not voice.
i have no clue but doubt there is any bias. but would be very happy to be proven otherwise as we know tape rec without bias isnt so cool.

so plan is to build impedance/amplification around it.
Simple start stop (even if its power on/off).
if possible motor speed (i suppose a potentiometer between the 2 motor wires at E12 E13).
head manipulation (maybe) a way to disable the erase and rec heads. (mu shield tape?)
on the pcb side, the erase head sits in the upper left corner. Theres also a grounding lug.

if some of your experts on here have ANY advices or are able to make sense of the pcb and signal flow, please enlight me.
i suppose the actual signal goes through the 2 little hammond (transformers?)

the whole unit is super small. Imagine width/length of nagra sn and probably 2-3 times the height.

the purpose is field recording, music recording, looping, delay (for delay i have a echo matic diy controller wich is build for 3 head tape devices)
i am not sure if the heads are mono or stereo.