Sounds like you have a lot of good stuff in place already and looking to fill in the gaps.
So as these are all variances particular to your organisation and they are over and above those required in regulation / standards, then I'd start with the name of the Regulation/Standard and have the engineers list the variances required against it. This will build you a register of company specific requirements per standard. If a standard is updated or an in incident occurs then you can review/update the register of variances accordingly.

The Management of Change procedure usually starts when a project makes it off the wish list, (so all stakeholders have an initial chance for input), so you could include an ENG/HS check that a list of variances per standard has been given to the contractors or if the job refers to a standard not on the register, that a review of the standard and a listing of variances is added to the register as a prerequisite of talking to contractors.

Do let us know what feedback you got from the engineers and other managers.

Reading the lists, these all look like items a project engineer should be responsible for specifying during their process of engaging the contractors such as completing an FMEA, doing validation and having independent inspector sign off.
IMO cherry picking requirements from published standards is a risky move, and the project engineer should be quoting compliance with the applicable standard(s) for the job the contractor is being asked to complete. Sure, you can write an in-house document for the engineering team, listing company preferred brands of component or types of fixings if that helps standardise the process for the engineering team.
For H&S purposes I would be looking at the overall process, if you want to document it.

• Have your engineers quoted published standards the job must be completed against?.
• Do the contractors have an H&S policy and (where applicable) use licenced staff (eg electrician licence)
• Is there an engineering, operational and H&S review before the job starts, during stages of the job and with each contractor?
• On completion are there engineering, operational and H&S reviews and signoffs (eg FMEA, validation, drawings update, inspections - electrical / HSNO have been done, staff work instructions and training completed, H&S risk register updated...things like that

I agree with Andrew above, that if you have determined your forklifts don't need to be registered or WoF'ed due to your site conditions ie closed site, private road etc, as discussed above, then an F endorsement for the driver is not needed or of much use to them.
The F endorsement is only any good to the driver when driving a road legal forklift down a public road.
Absolutely, get them trained and periodically reassessed by a registered instructor, authorize them to drive your forklifts and monitor their competency on an ongoing basis.

Yes we you ManGo as well