The splines on the Ididit columns are same as GM. I mounted the stock steering wheel in my '38 Ford pickup to a '77 Monte Carlo tilt column. The old Ford has a tapered column, no splines, uses a keyway and key. However, the taper of the GM column is the same as old Ford. Just machine a keyway in it to match the one on the old Ford column. Don't know what kind of steering wheel or vehicle you're talking about, just saying it can probably be done.
My 58 Impala steering wheel went straight on an Ididit tilt. I don't recall having to order/fabricate any special adapters or anything. Paul
Ididit now makes columns for ford wheels. I used one of the new ones on my 66 and it looks very stock and the wheel fits nice. The tilt lever is a shortened version of the factory turn signal level.