I'm getting back into the hobby after a long absence and have dragged out all my Bachmann rolling stock from the 80's.  I have a 4-4-0 American, a 2-8-2 Prairie, a minitrix 0-6-0, an Atlas 4-6-2 and a new Bachmann Spectrum 2-8-0; a collection of 1860's cars, a consist of 65' passenger cars, and a few assorted freight cars.  I'd like to convert them all from Rapido to magnetic knuckle couplers so as to make switching operations possible.  Can anyone give me the benefit of his experience here?