A small innocuous short-range passenger transfer vehicle is not mutually exclusive with "loaded to the rafters with weaponry".
At least not to any group of PCs worth their salt.
Han: So, Luke, the plan we've all agreed to is a full-frontal assault to blow up the Peace Moon.
Luke: I didn't agree to that.
Han: The first step is we load up as many guns as we can onto the Falcon—
Lando: You're not using my ship on a suicide mission! Don't we have a more expendable ship?
C-3PO: Wait, Wedge captured a shuttle, right?
Han: Okay, we load that up with guns and—
C-3PO: An Imperial shuttle.
Han: Yeah, so?
C-3PO: It looks just like an Imperial ship. Because it is one.
R2-D2: Great idea, Threepio! Perfect for sneaking in and seizing assets.
Han: We can still stuff it with weapons, right?
R2-D2: Hell yeah!