You’ve got a nice challenge here 
It’s not recommended to have different subjects on a memory palace you have already used. You can use the same palace if the subject is related to the one you have memorised. Else it would probably create confusion.
The best idea would be to have a palace, and rooms for each section, and place the images in the rooms, so you can visit it mentally and see each image.
If you insist on using your current palace, you may then think of creating a mental grid above each location, and use those as sections.
You can use a complex image on a single location-grid-section for each of your procedures which maybe a little more difficult if you are new to memorising.
Let me give you a quick idea on your first section with a complex image.
You’d have to mentally imagine this on your location grid.
Title: Abort Start Procedure
Keywords: PCL | OFF | STARTER Switch - AUTO/RESET
Images;
Abort Start Procedure Location: Your section slot
PCL: Cucumber Pickle
OFF: Light Bulb Not Lit, with a switch to Off.
STARTER: Switch to ON.
Auto-Reset: A Countdown-Timer
You’d need to imagine and visualize a complex image of the example below.
- On your Location spot
- Your Cucumber Pickle is like human with hands and feet. (PCL)
- He has his arms wide open on both sides.
- On his left hand is an OFF Switch with a Light Bulb Turned OFF.
- On his right hand is and ON Switch.
- His foot is kicking the countdown gadget, Resetting it to 00.
- The Bun in his mouth represent the digit 1 from number-rhymes (One-Bun)
- X = Abort
- Traffic Lights is Red, reminds you of danger.
I’ve done a quick visual of what I would mentally see on the first grid of first section
If you struggle; You can always create a Mind-Map of the sections, and practice it on the mind-map, also practice with Action-Recall. That should also work if you did it a few times, and you should be able to memorise and retain it.
Have you tried doing that?
You can try Chain-Linking new items to the ones you already have. I’m not sure if this would work well, but since you know your subject well it may work for you. The only issue with chain-linking is if you forgot one of the links, then you would cause some issues for yourself. So I would recommend you to create a palace for it, or a mental grid above your current spots.
Welcome to the forum!