can anyone tell me the difference between a 300 deluxe and a custom elcamino in 1965. thanks all

Looking at a sales brochure I'd say the interior was the main difference. The Custom model had different seat covers, different door panels and more trim on the dash panel.

The Custom model, based on the Chevelle Malibu platform, also had different wheelcovers and possibly more bright trim in the grill area. (I'm not certain of the grill area).

The optional bucket seats could only be ordered on the Custom model.

Generally, the 300 line of the Chevelle was the lowest model. Rubber floor covering, less bright trim and fewer availible options. Basically a base model car.