[Silverback]

The standard base on the right and the low seat on the left.
The low seat does not have a front mount.
It uses a metal finger that fits into the square boss on the frame, that the original seat mounts bolts onto.
The Rear mounts are short solid legs instead of springs.

Thank you for the pics.  My frame looks just like yours.  I dont understand what the difference may be. I have an email to hitchcocks asking about this.   There seem to be several different part numbers or kit numbers for these seats. 1990636 and   1990703.  Head scratcher.

[Haggis]

It may be down to the frame mounts?
Mine go in horizontally through the spring.
Some other years, especially the bullet have the mounts vertically.
The seat brackets have a 90° bend at the bottom.
Hitchcocks list the seat with three part numbers.
SEAT, SINGLE FOR C5 (UNSPRUNG) 2014 on (Can not be fitted with pillion seat) 1770007/1990636/1990703

[Silverback]

 thank you for you assistance and time. Your input and pics have really helped.
Mine are set up per your pic.  I just gave the modified seat a trial run. My butt back have been spoiled by the springs.  I forgot what it was like to be bumped out of the seat.  Before with the fully sprung seat over same terrain it was a smooth up and down. No jarring to the back and bum. I would want to also add some spring travel to the low riser seat. Making seat mid way between sitting on the frame and fully sprung. This little rise was an eye opener.    The lycett seat may be a better choice.  Looks like the spingarn in the seat frame provide more cushion. I read where one person put double layer yoga mat under the seat cover.  I guess that would eliminate feeling the springs.  Plus I won't have to worry about the pillion fitment.

Too many choices lol....

Although I prefer the lower seat height I dont want to feel the road. Lol...

[BB2023]

I have this seat, don't know what it's called it came with the bike.

It's hard with a layer of gel. I have sat on the original seat and that is way more comfortable but the riding position on mine is very good for me.

[MowgliB5]

The low seat tends to make you sit further back on the bike.

Oooooooh that looks a bit uncomfortable to me, especially for any long period of riding!!!
But I may be wrong?

[Guaire]

The low seat tends to make you sit further back on the bike.

Haggis - I got a lower seat then I changed my bars. It's an after market part with a large pull back.

Another way to effectively lower saddle height, is to cut down the width. To do that you need to remove the cover and foam. Then you cut the seat pan to narrow it. Then modify the foam and cover and re-assemble the seat.

[GlennF]

Compared to the 780 mm unmodified sea height of my old XJ900, all Enfield, even the 350 cc ones are quite high.

[Silverback]

I  modified my original seat to sit lower with shortened springs.  It fits and works with oem rack and pillion.  I used a simple U shape bracket to attach front of seat to frame. It allows for rotation.  Trimmed the back lip of the seat and reshaped seat pan to clear pillion attachment bars. Springs were cut to 3 coils.  It provides similar performance as original set up. Unfortunately the original seat foam begins to compress quickly and a little vibration in the crotch area.

I want to remove the cover amd foam material from my touring seat and put it in altered pan.  But I dont want to destroy the touring seat.  So I have a new set of original spings on order to do a comparison.   

I am still looking at a lycett seat.  I have to.measure as I think it would clear pillion attachments if lowered.

The lycett seat and lycett pillion looks like the user could modified much easier for height and comfort. I say this because the covers can be removed easily without destroying them.  User can add padding or remove suspension springs to adjust for comfort.

When looking at the oem seat pan I realized something.  It appears the seat is set up for user to seat more forward on the nose of the seat. I have been sitting with more if my weight towards the rear of the seat.  When you look underneath the touring seat the only area visible with the 3d material is towards the nose of the seat. 

Before I do anything else I am going to try sitting with.my weight more towards the nose of the seat with new springs.  It will cause me to sit super close to tank.   I know I am talking about an inch or so difference forward or aft but it makes a huge difference.

Lol.....I have too much time on my hands. I guess that what happens when you get old and retire.