I'm having lots of problems fitting the airbox on my '70 CB 750 KO. This is the early-style airbox used only on the 1969/70 KO's. The boots of the airbox are all the way on the carb throats, except for a small gap at the top part of the boot, which appears to be correct if one compares it to a photo in several Honda restoration books. But, I cannot get the top two upper mounting brackets to line up with the frame mounts. I'm off by about 3/16 inch off to the rear of the frame brackets. Plus, the rear of the airbox is jammed right against the frame tubes. It would almost seem that the cartbs are not fully seated in their cylinder head boots, but I've checked that, and they are fully seated, and the boots are fully seated on the intake runners, right up the to "hex" nut on the runners. I've also made sure that the airbox rubber boots are oriented the right way, with the wider part of the grove at the bottom of the airbox opening.
This is an aftermarket reproduction airbox, from Yamiya in Japan, and supposedly an accurate repro.
I have noticed that there are two styles of this early airbox offered: One with a 2-bolt upper mounting bracket, and the other with a 3-bolt mounting bracket. Mine is a 2-bolt type, as shown in the original Honda parts manual. What is the difference between these two?
Any help appreciated!