If you have the right tools and you can grip the bolt head, all it takes and a couple of turn and the bolt will snap off.
To answer your question about fitting it in your car. I usually pop off the cotton pins and remove the hood. Take out as many removable parts and but them in a box. The i slide the frame on it's side with the fire box still attached into my SUV. Was easier when I had my minivan. Get tight in my 3 row SUV.
this worked fine with silver b but concerned the older style is taller, so less room. Maybe remove the wheels too? Which I haven’t done in the past