I just finished up putting a ebay one in mine, if your looking to keep it in the same place as far as spacing from the dash then a 30" would be the minimum. I went with a 32" and have a little bit sticking out from the factory mount on the firewall, inside is the same as stock distance wheel. These have no mounts so you will have to buy one or fabricate a mount for your dash. They are also 2" in diameter and have a 1" DD output shaft. The switch for the turnsignals was a little cheap I thought but you get what you pay for.
One more thing they also usually come with a 9 bolt steering wheel adapter, so your steering wheel choices are limited unless you buy another adapter. I paid as much for a wheel as I paid for the column.