I remember those buggy kits very well. Unfortunately, I worked department management at Volkswagen/Porsche/Mazda dealers a few times, back in the day.
The buggy craze hit and people were buying those Meyers kits.
If I recall, basically, one had to remove the body from the floor pan of a VW Type 1 (bug), shorten it by cutting out a section and welding it back together, shortening the shift rod and brake/fuel lines, by that measurement, and attach the glass buggy body.
We were into off-road buggies with no body. A friend and co-worker, who could weld very well, helped me shorten a floor pan, build a roll cage from steel tubing, install glass bucket seats and belts, eliminate front brakes, install huge rear tires/rims, aluminum1/4 barrel beer keg gas tank, etcetera.
I weighed and balanced connecting rods on a balance scale, installed 1700 jugs on a 1600c.c. dual-port VW engine and put on a tee-pee exhaust header and Holley Bug Spray carb.
I actually raced (time trials) it a few times (still have a trophy!) That light-weight machine could fly, literally! The courses often had whoop-de-doos and other assorted terrain features. It was a blast to drive and race!
In the 70s Volkswagen answered the buggy craze with its own buggy, the Volkswagen Thing. It looked an awfully lot like a Kubelwagen (WW2 Nazi military “jeep”).
Thanks for the memory jog and brain farts. How I lived through 7 motorcycles, buggies, piloting airplanes, and ski racing friends in the Rockies, scuba diving, I don’t know.
I guess “What doesn’t kill you, makes you stronger.”( Except for bears and sharks. They will kill you! 
) Come to think of it, I still swim frequently with sharks and Kayak amongst stingrays. 
CSA
Used to work with a VW nut who daily drove one in the late 90’s, The Seattle Police weren’t so sure it was street legal sometimes though.
If you swim at the beach, you almost certainly swim with sharks. You just don’t know it. Apparently we aren’t usually on the menu.
Our favorite beach to visit on Oahu had a known population of sharks but unless you went further out you really didn’t encounter them. I believe the sea turtles were more appetizing to them. The local morning news has had a helicopter over Waikiki Beach showing three or four tiger sharks swimming close to the beach.
When I lived in Santa Monica I swam every day warm enough, a mile down the shore to Venice, then walked back in the shallow water. I stepped on a little sand shark once, skipped away and kicked a ray. A dolphin showed some interest in me when I was swimming once.
I thought a vehicle originally designed with a roof needs that roof to keep the vehicle’s body from twisting as it encounters imperfections in the road like potholes. When a person cut up a VW Beetle for use with a dune buggy body, did they add frame reinforcements to compensate for the lack of a roof?
Did you stop and play with it?
By shortening the chassis it becomes stiffer, and the added bodywork also helps stiffen it. They’re very light, so the loads are reduced, too. Finally, there are no doors that need to match their openings, so some chassis flex isn’t as noticable.
If I had wanted to play with it I would have tried to keep up with it, which not even Michael Phelps can do. It swam by me and seemed to look at me for a second, though I may not know where a dolphin’s eyes are pointing.
Yeah, certainly it would have to want to dawdle too. God thing it wasn’t an orca.