Vintage Ploprof advice appreciated

Hi All

I am a collector of vintage dive watches from the 60s and 70s and hobbyist watchmaker. Although I only just joined this forum I have been on the hunt for an unmolested Ploprof for a couple years. I recently picked up this early generation example that appears all original. Judging by the condition of the dial and hands and the melted gaskets I'm guessing it's never been opened. At least I'm hoping to find it's original movement inside!

As this is my first Ploprof I have a couple questions for those who may have worked on one of these beasts;

1. Any tricks/pitfalls opening up the case?
2. Advice on extracting the movement without contaminating the dial with the dreaded gasket goo?
3. Does anyone have the service manual for Omega cal 1002? I've searched and found a general guide but not one with a detailed exploded view.
4. Part numbers for the crystal and crown gaskets?
5. Keep or replace crystal? I usually replace preferring an unimpeded view of that gorgeous dial but for the sake of originality I'm not sure with this one.

Any advice appreciated
Cheers

Nice early Ploprof. Do you have pictures of the back?

To remove the mouvement you need to take off the bezel with a knife then unscrew the crystal.
The crown is not a ratchet one don't pull it off.

That dial is very nice at the moment, and the seal has melted to a dangerous level. I would be very careful and advise giving it to someone familiar with these if you are in any doubt. It would be a shame to contaminate the dial.

something to be aware of if replacing the crystal is that Omega no longer produce the crystal in mineral, it is only available in sapphire. Ref 062SN5319

Here ya go...