Difference between 1987 Electraglide and 1994 Road King front end

[BEAST_DC]

Hello all. I am new to this forum and also new to Harley touring bikes. I am about to purchase a 1987 Electraglide Police model. I was hoping someone would be able to tell me the differences between the 87 E-glide front end and say a 94 Road King front end. Reason I am asking is I am looking to purchase and install an aftermarket batwing fairing, and all of the ones I see are made to mount on Road Kings, softtails or metric bikes. Ive sent emails to manufacturers asking if they would possibly work for the 87 E-glide but they all say they wont. I have a hard time grasping, there being that much of a difference where it wont work or at least work with minor modifications. Thanks in advance for your replies, any help will be greatly appreciated.