Fill in the blank riddle

I have the following two sentences that contain 4 variables (W1, W2, W3 and W4) between them. I must figure out what each missing word is, and the only information I have is a range of possible word lengths for each variable.

The puzzle:
1. There is a W1 in the W2 W3 is near where the road bends which contains very important items.
2. For W4, the top of the W3 is on the counter.

For each variable/missing word, here's what I know about it:

W1 is 6-8 characters in length
W2 is 3-5 characters in length
W3 is 3-5 characters in length
W4 is 6-8 characters in length

My first inclination is that W3 is either "which" or "that":

o "There is a W1 in the W2 which is near where the road bends which contains very important items."; or
o "There is a W1 in the W2 that is near where the road bends which contains very important items."

But W3 also exists in sentence #2 and neither which/that make sense for it:

o "For W4, the top of the which is on the counter."; or
o "For W4, the top of the that is on the counter."

I'd be enormously happy to get any-and-all help for all the 4 variables, but specifically I'm really stumped on W3. It's a word that has to be both a noun (something that has a "top" to it) and a connector that is similar to which/that. Any ideas? Thanks in advance!