Can anyone please tell me how to align the car blueprints in ProEngineer?

with the Style tool (ISDX).
Its very complex, but, a powerful tool. you can import the blueprint, select the follwing :

Styling ( top menu ) : Trace Sketch : Select your plane F/R/T : Choose the blueprint from saved location.

Once you have inserted the blueprint, you then have to rotate and move to its desired location.

Hope that gives you some idea

and the second way is useless but it works if u have not got ISDX

create a surface and apply your image as a decal to it,
just be careful not to reference it otherwise you cant suppress or delete it.. thats all