I'm building a rocket with radially attached solid fuel boosters that have extra liquid fuel tanks on top. I desire that the solid fuel boosters decouple and leave the liquid fuel tanks attached for later decoupling.
I cannot get both the stack coupler and both radial decouplers to attach all at the same time.
I've tried several methods of constructing it. One method joins the liquid fuel tanks first and tries to attach the boosters to it, and that doesn't seem to work at all - the top join point on the boosters doesn't connect to the bottom join point of the coupler. I can attach both parts separately with radial couplers but if I don't use 2 on the solid booster it wobbles both on the launch pad spawn and in flight. If I do use 2 radials on the solid boosters, they decouple weird and take out my liquid fuel engine at separation.
If I construct the whole side stack first and then attempt to attach it to the main rocket via the bottom radial coupler, the top coupler doesn't attach and the whole booster/tank assembly wobbles on the one attach point.