[OpelGasser]

As many of you already know I am planning to move back the firewall on our Opel.

It is something that really needs to be done not only for giving us a better seating position but also much needed "space" between the existing firewall & the headers.

As it is now there is practically NO CLEARANCE at all which causes extreme heat to be transferred into the interior.
This picture tells it all..... melted the Dynamat right off!!!!

As so often happens..... changing one thing causes other changes to be made. Moving the firewall back will COVER-UP the window cranks on the doors. I could add power windows but being the car is an ex-drag racer I want to keep that look as much as possible.

While looking at pictures posted here I noticed "Old Coyote's"

Two Lane Blacktop styled "sliding side windows"

I would appreciate any info or suggestions anyone can give me about doing this.

 

[1937Austin]

A friend did this on his car year ago. Your car will be easier as it has fairly straight lines on the window openings. He used regular extruded aluminum window channel designed for sliding glass that has no edging on the glass. The inside trim needs to be modified to allow for the wider dual channel, and a piece mounted top and bottom in the door. One half can be installed fixed, or you could make both slide.
My friend had a '55 Chevy and he had a small chrome knob to grasp to slide the rear half forward, or the front half back. He cut away the window trim to allow for it to be reinstalled. Not sure if the Opel even has interior window trim, so you may have to figure out how to dress the inside edges once the upper and lower channels are installed.
If you can't find dual aluminum channel you could get 1/4" channel and have two tacked together on the back to make a dual. 1/4" channel is pretty easy to find and not too pricey.

 

[maddog3299]

If you want to do a junk yard crawl, some of the 1960's - 70's vans had sliding side windows. That would give you the upper and lower track that Vall is talking about and made not so labor intensive. Or even the newer rear sliding windows for pick up trucks.