retrofit

Non roller trucks are cheaper. Why not save them for cars that can use them?  (you'll likely find a need two days after installing 🤣)

As far as a coupler goes, "off with it's head". 

  I wouldn't bother with chasing something I could cut off without anyone noticing.  (I'm also not the type to detail an undercarriage I dont see until I flip the car over... milage may vary)

When swapping trucks that aren't pairs, be aware not all trucks look exactly the same, even if they model the same truck. The heights can differ as well, and raising a (already too high) car on washers may be needed to get level.

  I.e., I like to swap in matched pairs to avoid puttering around with some of the variables.