Three prong headlight socket

[John m kelly]

Hi I am putting a cycle Ray headlight together. I acquired a reflector without a socket. I purchased a new 3 prong socket and had the reflector resilvered. Is there a trick to install the new socket in the reflector. I am able to get 2 prongs in but the third it seems will have to be forced. Is that the procedure. Also the original socket had a third wire for a ground. My new socket does not have the third wire, is it necessary to attach another wire for the ground.
Thanks. J Kelly