Alan, that Fireball 500 trailer really fits the Mooneyes dragster, at first glance I thought it was scratch built. I got the Cube as well. As jb and others have pointed out the variations on the Mooneyes dragster changed almost every time they ran it!
My Cube comment above more so refers to the fact I'm not a fan of the Cube in the first place. Looks too cutesy, cartoonish. Like the designer tried too hard to make it look like it came from a Manga comic.
I did put a weber on my Mini-Sprint. ONE weber! It fit OK. I have read that whent the 1-1 Minis get webers they have to cut a hole in the dash so they stick into the interior a bit!
There is an "Air Box" sold for that, the hole in the back of the firewall is already there and has a blanking plate fitted over it. The "Air Box" fits into that hole and seals off the back of the Centre Binnacle so that the sucking noise from the carburetor stays on the engine side of the firewall. I've never fitted a Webber to a Mini / Spridget engine, but I understand they are a bear to tune properly. You see Side Draft Webber 48 IDA's on dedicated Race Engines that primarily run high RPM's pulling huge amounts of air through the motor. On a street & track Mini / Sprite / Midget you see mostly SU's and some recently running the Mikuni motorcycle carbs. For "Hot Street" a whole lot of Mini's are running the 1-3/4" Bore SU they pull as much air as most of the smaller bore dual carbs. With stock crank shaft and main bearing configuration Mini engines are not a high RPM Motor, which is why the Weber is difficult to tune to a small motor. They look cool though!
How thick is the Bonnet? Could the thickness be contributing to your issue with the bonnet not properly closing?
What about removing the head from the block and shortening (decking) the block enough to gain enough room to make it fit under the bonnet. Removing the material from the block would probably be the least noticeable place to remove material, the height of the head would pretty much disguise it.
I'm sorry if this seems "mean", but understanding "scale" only requires an understanding of fractions and division. This is fifth-grade math. How can anyone functioning in society NOT have these basic elementary-school skills?
Bill, it's called "Dumbing Down". Johnny or Susie can't understand how to do it so they stopped teaching what kids didn't understand. That's why all the standardized testing is huge in the world of education right now. As in the U.S. Education system is trying to play catch up with the rest of the world who refused to stop teaching the basics, they just found better methods to teach kids in ways they understand. (My wife is a Teacher, I hear about this stuff almost every day!)
I've used a standard old calculator forever, most of my measurements are made with either dial or digital calipers or a machinists rule (hundredths). So converting the measurements to decimal just makes the whole scaling up, down all that much easier.
Accuracy normally boils down to how many significant digits beyond the decimal point you wish to take it. Even with digital calipers styrene has enough give to it that there could be some loss of accuracy as no two people measure with the same amount of pressure. In scale modeling hundredths of an inch is probably more than accurate, unless it's metal thousandths are just overkill.
The key to accurate number crunching is to allow the significant digits to float throughout the calculations, then round the output to the appropriate significant digit, which would be the last mathematic calculation. Most decent calculators can be set up to float the decimal point, they do it throughout the calculations though; so there could be a minute amount of loss of accuracy.