I would swear that MIP made a set but I can't find a 'definate' on their site. I'm going to assume that the XXXT bones are the same but I can't say for certain. Drop them an email and I will ask at the LHS today.
actually when i bought mine the packaging said it was for the xxx/nt i think the xxx/t has a skinnier track I'm not sure i dont know much about the electric version but like i said the ones i bought said they were for the xxx/nt
also if and when anyone buys these one tip on the roll pin that goes through the pivot bushing is round and the set screw that holds it all toghether is flat save yourself some headache and file a flat spot on the pin it will allow the set screw to hold much better and the nice thing is with the flat spot you wont have to go looking for another roll pin when the original falls out