Should you get a 141/181 in the future , I would suggest that you solder/hard wire the speaker cables to the PCB as shown in Flange Lubricator link / photo below.
Yes , you can solder speaker cables to your sound decoder.
I would not recommend to solder cables for speakers on the sound decoder as you will have to unsolder them in the future to fit the sound decoder in the A Class and also the sound decoder may get damaged aswell from the soldering which may also invalidate the warranty too.
It should be interesting to a 141/181 as it is 12 cylinder instead of the 8 cylinder sound .
I must try this on the next club night