jacuzzi drain removal

[corney]

I'm trying to remove the drain assembly from a 15 to 20 yr. jacuzzi. Only brand or model is the name"ALMICO in large block letters followed by "Comfort and Elegance in flowing script on an escutcheon on the tub lip..
This tub has a cable controlled stopper operated by a half turn of the overflow fitting. I have tried turning the drain by inserting a removal tool down into the drain to no avail.By looking in under the tub I can see a large nut under the drain unit but I'm completely baffled by how they originally installed the tub as there is not sufficient clearance twixt the floor and tub bottom to get a wrench in there let alone a hand..
It would be great if someone recognizes the brand or maybe knows the RE.& Re, procedure for this type of drain..I myself have never seen a cable controlled stopper like this one..
Any tips or suggestions would be greatly appreciated. Thanks for your interest....CORNEY

 

[Hackney plumbing]

Take a pic of it looking into the drain from the bathtub where the water drains out. Remove the stopper then take a close up. There may be a nut there you can un-screw counter clockwise. Its about 3/4" in size.