Great looking El Camino. I wonder about the height of the seat backs. Visually they look a little tall especially the head rests. Clearance may be an issue with the rear window as well. I'm sure you will work it all out.
The smooth rear wheels seem out of place. Most of the wheels of this design that I have seen usually have some sort of a cleated tread pattern. These look like they would just spin and not go anywhere in any muddy field.
I don't remember which member it is here but they're doing a French Citroen. Find a Rolls Royce or a MB maybe. There used to be a real nice Volvo Shooting Brake (wagon to us) kit. Hillmen Minx or a Morris Minor maybe?
The H78x15 was the way they stated the tires size at that time. The H designated approximately the older 7.60 size and the 78 was what they call the aspect ratio between the tire width and the sidewall height. The tire tread is 78% of the sidewall height.
Beautiful looking paint color and finish. The chassis conversion looks like an OEM level design that should have been originally. The custom interior looks great and well detailed. The wheels really work well on this.
Great build idea, especially for a kit that some goofy body proportions anyway. Like your approach to the roof. Your well into that now but wonder if the El Camino roof section from an old AMT '55 Nomad might have been an option for this.
Start with an 800 grit and work your way up. I have noticed that some of my Tamiya paints, regardless of color, seem to get a little unpredictable when they have set around with maybe 1/4 of the paint still present.