Sram S-7 and 9.0 group set - Segmented Compressionless housing replacement

[Sramcialized]

Hello, can someone help guide me to DIY replace the housing on a segmented shifter cable for a Sram group set?

It's a Specialized P3 dirt hopper, probably about 20 years old.

The shifter worked ok but the housing finally jammed up near the shifter (see pic)

I am on a tight budget and need to DIY this one. I am capable but am unfamiliar with replacing the shifter housing. I believe it's a compressionless housing. A bike shop locally will charge about $50 with labor and materials, which is a great deal, but I am looking to just buy $10 in parts off Amazon and DIY, using an Amazon credit tucked away for this rainy day. I also cannot easily leave the bike in their possession for days on end, given their turnaround.

The rear housing segment seems to be in okay shape, and the cable itself is in tact. So, really, if lucky, can I just replace the front housing segment only and leave the cable in the shifter? I'd prefer not to open the can of worms inside the S-7, under the understanding that it's advisable to replace the cable at the same time as the housing (segments).

Is there a way to get a pre-fabricated housing segment with the caps at the correct length? If not, can I get away with standard tools since I am just cutting the housing and not the cable? Is it possible that I just need to remove the rear segment, remove the (broken) front segment, leave the cable in the S-7, then run a new front segment prepped to the same length as the old front segment, add the rear segment and re-attach the cable to the 9.0?

I am capable of doing the repair myself but am hoping someone can give some positive feedback on a viable approach with standard tools and a housing from Amazon.

Thanks,
Sramcialized

 

[Ajax Bay]

What you propose is fairly risky as there's a high chance the inner cable needs replacing.
Even IF the inner is OK and you left it in the shifter, the end where it's clamped is well bent and you would struggle to thread it through new sections of outer, really struggle.
A new cable and a section (eg 1 metre of outer (all gear cable outers are 'compressionless)) will be inexpensive (eg <$7).
Youtube is your friend.
Make sure you release the trigger shifter down to highest gear (smallest sprocket) before taking off the shifter cover. It will be visibly obvious where the cable needs to be threaded in/through.
You will need cable cutters (pliers will be inadequate).

 

[DCBassman]

Can only agree with @Ajax Bay . New complete cable time, and if at all possible, invest in the correct cable cutters. Not only will they last a long time, they will make the job simpler and quicker.