is there a difference in a hx35wg and non wg housing flange?

 

The flange that bolts onto the exhaust manifold is the same.

 

what about on the dp side?

 

Yeah, that's the same size flange too. You just take off that elbow from your wg housing and clamp it onto the non-wg housing.

But remember that non-wg housings are almost 1" shorter front to back, so you will have to either loosen your down pipe below and try sliding it forward, or splicing the exhaust to make up that 1".