The antique fire truck is a Mercury model. Mercury was the prominent models for trucks in Canada where Ford was United States.
Jack and Jo find the PEG bottle by a path. There are some weird points. The chemical formula for polyethylene glycol is correct (reversed from the norm, but correct) yet the structural formula is wrong; the bottle is labeled "Prescription Only" when PEG is not restricted; the bottle is actually a canted neck, 75 cm2, tissue culture flask which would never be used as a commercial reagent bottle even though most tissue culture labs use them to store homemade reagents.
Writers slipped in a cute joke they set up in Zoe's chemistry lab to the explosion at the laundry cleaners. Adam Bergquist plays Zoe's chemistry teacher Mr Hall. Mr Hall is lecturing how deviating from a chemical formula (in a lab experiment) can result in chaos. The class knows Mr Hall is passively noting Zoe's failed chaotic lab experiment which is overflowing its container. Two scenes later, the dry cleaners explodes. Dry cleaner (former chemist) Callie Curie is asked, "What Happened?" by Sheriff Carter. Callie surmises, "I don't know. I must have measured wrong." The very subtle joke goes back to Zoe measuring her chemicals wrong -of course, the true cause is more complex than measuring the chemicals in her formula incorrectly.