Stock air box installation

I own a 1979 Kawasaki kz750. How do I install a stock airbox? Ordered one off eBay and can’t seem to get it to fit.

The carbs need to be off the head first, you can leave the manifolds on (I am assuming your talking about a 4 cylinder) then there should be enough room to slide the air box back between the frame rails. Then you remount the carbs back on the rubber manifolds.

The last thing that goes on are the rubber ducts between the air box and the carb mouths, the easiest way to get them on is thru the top opening in the air box, squeeze them thru the openings on the front, use some WD40 or similar to get them over the carb mouth ends.

A 1979 KZ750 B4 is a twin. Are you sure that the box is for a B series and not the K or M?

Carbs and manifolds are off and I still can’t slide it in. Must’ve been sold the wrong size 

Guy on eBay said it was for the twin, must’ve been wrong though cause the carbs are off and it won’t go in 

The KZ750 B, G, K, and M are all twins. The B and G use one box, the K and M another. You may have purchased a box a K or M twin.