The main choices for a straight 3/4 shaft is the Moroso style 3 bolt push button style that uses a hex or the Strange 5 bolt style that uses a splined adapter and a flange that is pulled toward you to release. Similar models of both styles are sold by many different folks. The splined 5 bolt style is more money and is the higher end piece. I would use the 5 bolt style so you can use a Grant 5 bolt racing wheel without an adapter. A 3 bolt unit requires a cheapa$$ sheetmetal adapter and crappy rubber boot or billet adapter to use a Grant 5 bolt wheel. You may have an old 3 bolt wheel that would work on the 3 bolt quick release. And I would get it from a quality parts place and avoid no-name ebay stuff.

Grant offers disconnects and kits to use on stock shafts with the original splines. I don't see one for your application, but I would make a call to Grant to verify what they offer.

Up to you if you want to keep the stock shaft. I haven't done the switchover to 3/4" tube on one of those and would need to have one in front of me to see how involved it is.