the dohc ZC is a bolt in affair for the 88-91 hatch...
if you have an 85 crx what you want to get is the 86-87 brown top D16A1 dohc integra motor...
the 88-89 black top has 118 horses compared to the 86-87's 113, but if you get the black top you will need to change the distrubutor and such things
86-87 junkyard integra is the best bet... it would help to get the whole car
you will need the integra spindles, discs, calipers, axles, tranny, motor, ecu, and mixed mounts between the crx and the integra...
shift linkage is also helpful but not necessary...
your shifter will sit further back, so first gear would be where 2nd used to be and 2nd will be back even further
takes some getting used to but its not that bad...
you will be pretty happy with this swap and you won't be dumping a lot of money into a car thats that old...
check the forums... either refrence section or articles section for the first gen crx FAQ... it has a little more detail...
and PM me with any questions or search for my pics in the gallery to see what it will look like
good luck