i dont know much about crx....just that my friend's tranny is messed up and hes gonna replace it...so we're wondering if a sohc zc tranny can fit to his stock d16a engine?.....or will there be some modifications?

 

Unsure if the SOHC has the same tranny as the DOHC, but if it does then you do have a little more than just a tranny swap.

Axles are different and will require you to remove the dust seal off the inside of the wheel bearings (same you will find with the B-series swaps).
May have to tap threads into the back of the engine block to hold the intermediate shaft on the driver's side.

Alternatively, you can swap out the oil seals and diff out of the Zc tranny and put in the ones form the old tranny so you can use the regular axles.

 

SOHC and DOHC ZC trannies are different. I believe the SOHC trannies are just Si trannies, but the DOHC ZC trans is the one with the bigger axles and the one that uses the intermediate shaft.

either transmission will bolt right up to your D16A6 and all your plugs, starter, clutch cable, etc will work just fine. Like I said though with the sohc zc your stock D16a6 axles should work fine. The DOHC is a different story.
Good luck