This isn't good news. I didn't think a 1:24 Alternator/Binaltech could fit in the MP10 trailer. So it'll be significantly smaller but a hefty 6800 yen.
MP-10 is scaled more with Alternity/Classics. The Spike figure as well.
I just tried getting Alternator Meister RX-8 in MP-10's trailer and it does fit, with less than a millimeter to spare in length and width...