I just made a ported box, and the recessed terminal cup i bought at my local shop looks pretty hard to install - the back of it is a rounded rectange. is it ok to just drill a small hole for my speaker wire in the back of the box and fill it with silicon caulk? im worried this will just make it leak terribly...

no it will be fine, just drill the hole where the wire fits snug in and silicone it from the inside before you mount the speaker

just use 2 bolts as the terminal. one for pos, one for neg.

you wont have to worry about the silicon coming loose

You could, what you could also do is drill 2 holes slightly smaller than 3/8" and then use 3/8" bolts to attach your wires to. use some wood glue and then thread the bolts through the holes.

I use the hole + sealant technique and have never had a problem. Bolts work too, but you just have to make sure that nothing might drop on them, get pushed up on them, etc., that might make a connection between the two.

Lazy people like me run them through the slot.