Many Invacare TDX power wheelchairs will have almost identical instructions - but keep in mind each wheelchair user's needs are unique and they use their chairs differently.
Ideally, it is easiest to mount when a wheelchair is not occupied.
Optional:

Please follow the:
from Step-By-Step instructions for the Invacare Storm before performing the steps in this document.(These directions can replace Steps 2, Steps 3 and Steps 4 of the Step-By-Step instructions for the Invacare Storm).
The rest of those instructions apply to both the TDX and the Storm wheelchairs.
When you are done with these instructions, please refer to Step-By-Step instructions for the Invacare Storm: Step 5 and onwards for a complete installation.
This picture shows that the screw has been removed.
The removed screw has a spacer sleeve on it.
Remove that from the screw and place it somewhere safe - we will need this spacer to hold the cap in step ***.
Screw #1 needs to be re-inserted so that the wheelchair seat cross-member does not shift out of alignment, which would prevent proper re-assembly
using screw #1 that we just removed the sleeve from - re-screw it into the same hole.
Make sure to leave out the cap when you screw it in.
Using the 3/16" hex key, screw #1 should be inserted as far as it can - to allow the insertion of the T-Nut.
The screw does not need to be torqued down tight, but the screw-head should sit relatively flush with the track
The rear-side of the rail should have the bolt threaded thru, ensuring the cross-member does not shift.
The spacer sleeve on Screw #2 needs to be removed so that the T-Nut can be inserted into the track.
Using the same 3/16" hex key, remove Screw #2 completely.
Remove the spacer sleeve and re-install screw #2.
Once screw #2 is re-inserted, both bolt heads should be relatively flat in the track
- allowing the insertion of the T-Nut.
Remove Screw #1
Insert the spacer sleeve onto Screw #1
Insert the cap into the track,
Using the 3/16" hex key - attach the cap with Screw #1 (that has the spacer sleeve).
The next step is to attach either more wheelchair mounting hardware (for offset and spacing) or a Wheelchair Bracket!
Proceed to Step #6 : Attaching the Wheelchair Adapter Plate to continue...