Merkur Futur troubleshooting

I have been using my Merkur Futur since I switched to DE shaving about 5 years ago and have never looked back. However I now realise that I have overlooked the care and maintenance of the razor and as a result cannot now move the head to adjust the setting at all. It's stuck on 2 which is generally fine for my beard with Feather blades but I would like to use other settings now and again.
When this happened a couple of years ago I sprayed a little WD40 and it freed up the adjusting mechanism but now nothing will budge it. I've read recent threads about disassembling the razor but there is no way I can turn the handle to 6 or beyond. Has anyone else had the same problem and how did you solve it?
One other question. As I've only used the Futur for the past 5 years, I have got used to the weight of the razor and (sorry guys) have to admit that it's the only safety razor I own. I'm looking to acquire a couple of other razors - can you recommend any of a similar weight that would perform as well as the Futur has done?

Just treat it as if you are restoring an old razor:


A good soak in water straight from the kettle with some detergent for a good 2-3 days.

Refresh the water periodically with new hot water (giving it a bit of a scrub with a toothbrush while cold).

This should hopefully work the scum out.

I have also used vinegar in my Vision. I would completely disassemble it and make sure all of the pieces are submerged. I LOVE the razor, but the maintenance kinda stinks. I suppose that is the cost of having a sweet razor like the Futur or Vision.