Frame dimensions

What do the measurements have to be to fit an engine inside a frame?The bike I have is a K2 Seaside and I don't know for certain what I need for frame dimensions.I see reference to 15" from crank to top bar.This bike is 15" from center of crank,but it has a front derailleur.That cuts the space down to about 11".this is the older style Seaside LWB and does not look like the one built today,it's cool.
If I can't use this bike I will be looking into something with similar style.Sure wish someone had a real v-twin 4cycle that could be mounted on a bike frame.I would not hesitate to start building.

Just after I posted I found the template.Now all I need is some ink in the printer.lol
This engine template will help alot of builders who are using a frame that is close in size.I am going to print it and make cardboard or some other type of stiff backing to attach it to.

Thanks for the reply man.