I am in the process of rebuilding an old gooseneck trailer I just purchased. The gooseneck setup is the old style gooseneck setup (ball rotates with pin through gooseneck) and I am looking to change over to the modern 2-5/16 setup to match my other trailers. Current setup is 6-inch channel iron coming from the trailer together and welded to a verticle 3-inch pipe cut in half. The half pipe (verticle) is welded to a 30-inch 4-inch diameter verticle pipe that goes on the ball. Text picture, verticle view- “-cO” where “-“ is channel iron, “c” half-pipe and “O” 4-inch pipe. Yea, that’s gonna make sense to yall without a pic!

Anyways, looking at changing the setup to 2-5/16 setup and have the following options:

1) Remove the 4-inch verticle pipe at the half pipe and weld on new adjustable gooseneck setup.
2) Install a 2-5/16” coupler on the bottom of the 4-inch verticle pipe.
3) Purchase an adjustable gooseneck setup, and install the inner tube/coupler in my current verticle pipe. I would have to weld/cut existing pipe to make it compatible with new setup.

To make things a little more complicated, current tailgate clearence with the gooseneck is just shy of 4” and trailer sits level when connected. Obvicously the adjustable could increase easily to 8” clearence with minimal impact to trailer leveling. What is the minimum tailgate clearence you recommend for a gooseneck setup? I don’t want a torn up tailgate!

What are yalls ideas / great thoughts on my gooseneck conversion options? Next debate is whether I want to take it to a trailer shop for $65/hr labor plus parts or just buy the parts and take the trailer to a friend who can weld. Thanks for the help!