I've tried both #740 standard shanks and #743 long shanks.
Long shanks look unnatural in their own right but still, IMO, are worth doing to be rid of the claws.They provide almost no reduction in car spacing over the claws.
Standard shanks are too short, likely for ANY curve! They require considerable compression of those not-so-flexible diaphrams. Immediate derailment on O-72! A real nuisance to decouple as well.
How far one wants to take this is personal opinion, of course. Mounting a long shank on one end of a car, and a standard shank on the other results in spacing "about right." Car spacing is much reduced and O-72 curves are not a problem. I think I'll just leave the cars I put the standard shanks on alone at this point and couple them to a long shank. If it gets to be a nuisance decoupling, I'll put long shanks on all.
Doing the conversion requires removing the car body to dismount the trucks. This means a bit of fiddling with the connections for the illumination. Then hacking the coupler tang off with a mini hacksaw or Dremel tool. It is not hard. But there is no way back!
I'm glad I did it. All my 21" GGD cars and now these 18" MTH cars are now "KaDee'd."
