Well, my 94 2.3L only had the diamond on the oil pump axillary gear, but not one on the motor/cover itself.
The timing cover and crankshaft pulley will need to be installed in order to line up the hash marks on the crankshaft.
You want to align the TDC marks for each gear, including the camshaft, crankshaft, and aux gear. Confirm that the crankshaft is at TDC and that the camshaft is at the 5-oclock position.
As for installing the belt, check out the link in my signature, but here's an excerpt.
54. Ensure that all timing marks align to TDC position, start routing timing belt starting at the crankshaft sprocket. Remove all tension between crankshaft sprocket and oil pump sprocket and route timing belt around oil pump sprocket. Remove all tension between oil pump sprocket and camshaft sprocket. Route timing belt around camshaft sprocket. Route the back side of the timing belt around the tensioner pulley and loosen the tensioner adjustment bolt - tighten adjustment bolt and spring bolt (17mm).
Place crankshaft pulley slightly onto the shaft and rotate the motor two full revolutions by hand (and make sure your timing marks still align - if they don't, repeat step 54).
Remove crankshaft pulley from shaft.
Tighten down all parts (such as the crankshaft position sensor) that you had previously removed and re-install any components to the crankshaft that you had previously removed.
Install the outer timing cover.
Install the center crankshaft pulley bolt (reverse of removal) and torque to 103-133 foot-pounds.
Install the four crankshaft pulley bolts.