I converted from my stock 4 speed w/OD to a 5 speed using a "Healey 5-Speed" transmission conversion kit from Pete Delany. I actually bought the kit from the original owner, Smitty, but didn't get around to installing it until Pete had purchased the business. Pete was extremely helpful once I got around to installing the kit. I will add pics of mine at some point, but rather than reinvent the wheel I will direct you to a great write-up of the conversion project by Tracy Drummond (Link to project). Tracy's write-up hits on everything that I did.