Rear seal replacement

[Ian France]

Hi again from France
Summer is over - the yearly deluge has arrived and yes my loved one (1983 911 SC Coupe ) is leaking
Thanks to all you pelicans that have written about leaks and seals – what an amazing source of information – I was completely lost as to how the water was getting into the back of the car then lifted out the rear seats cut away the sound proofing as recommended and discovered the secret swimming pools
So now dremel work and rust proofing completed its replace the rear seals time

From the many posts I could find on this I believe ---- This is going to be a SOB (I am complete amateur nervous but determined ) and believe I should
1) Cut the old seal from the inside of the old trim to release same with minimum/nil bending (sounds like that may be easier said than done )
2) Use KY jelly -that`s gonna start some fun gossip at the village (population 250) store ! - to help fit new seal to glass and to get the trim into the seal
3) Put the seal on the glass then the trim into the seal (using a shaped toothbrush handle to open the trim channel ahead of the trim and /or a pre inserted cord to help pull the lip over the trim barb – (same theory as inner lip over the weld when installing into the car only using thinner cord) – all on a padded bench
4) For the wiring – To also install this into its channel away from the car and to cut oval holes between cable channel and glass about 3 inches below /above the heater connections as appropriate to allow the wires to connect as parallel as poss to glass and another hole through bottom left of cable channel to pass the wires through to the engine space
5) Take great care with the heater connections as they may break if bent
6) Install the screen with seal trim and wires in place into the frame poking the wire ends down the hole in the firewall into the engine compartment and using the forementioned cord system to pull the seal lip over from inside

Can you guys with more experience of this please confirm the above is the "right" way and advise if there any other “tricks” / stuff I should think about ?
Also
A)How do I get the old screen out safely and how brittle it is likely to be (1983 original glass ) when I had a glass shop do the front screen it cracked a week later (could be coincidence but ..)
B)When inserting the screen into the car is it top or bottom first? (have seen both stated )
C)Same as above ref cord (overlap and start/finish at top or bottom?)
D)Are there normally connectors between the cable loop and the wire run in the engine compartment –my cables are bundled together and taped shortly after they get into the engine compartment (by prev owner ?) and would rather not open that pandoras box - if no connecters already thinking of cutting and inserting same before wires join the bundle so can still fit the wiring away from the car
E)Do not think much water getting in through the back (fixed) quarter lights but seals look pretty rough so may do them at same time but can find no details on doing these other than “as for other windows” and they do not look that simple to me (is there a clip of some sort holding the lower front corner of each ? –looks like having them out first may make it easier to manipulate/install back screen ? – but same questions arise about how to get the existing glass out safely and front or back in first etc?
All help and comments greatly appreciated

Sorry about the length of post and blatant idea stealing from other posts but hope it may also help other beginners having all the tips in one place

Thanks
Ian