Moving specialized MoW equipment & FRA rules

So there are 5280-odd FRA etc. rules on rolling stock: coupler strength, brakes, roller bearings, whatever....

There is also a Warehouse 13 full of specialized maintenance equipment used on, and moved via, said same rails. I'm thinking not just cranes, flangers, rotary snowplows..but also ballast tampers, and the {?Sperry} track alignment testers and such. But even wheel-equipped pickup trucks would be in the collection.

What rules [don't] apply to them in use? I'd assume many; I don't need a litany, just general affirmation.

NOW... what about transporting such items from X to W to Z? Some will be self-propelled, others hauled by an engine. Is there a FRA rule category that fits them, one giving wider latitude to such?

I ask because I was wondering how various transit systems [WMATA, BART, etc] dealt with their occasional need of such. I'd assumed they rented same; in the case of the bigger items, how else can they realistically move than on their own wheels?

MoW equipment is excempt from rules like locomotive inspection act, or CFR 49.229 . they do need to be inspected as far as brakes lights etc. but pretty much all come under the rule " if it moves and stops its legal".
All track equipment is moved under same rule, no matter if its a hi-rail truck a sperry car or any other MofW equipment.
They use a pilot (foreman or conductor) to move as per rules.