it will bolt up to the transmission, intake and exhaust, no problem - you will need to take the driver's side mount, that bolts to the block, off your old engine and swap it onto the D16A - the D16A should have the MAP sensor on top of the throttle body, where your Si had it on the firewall - you need to unplug the connector from the MAP on the firewall, extend each of the three wires slightly so that it will reach the throttle body and plug it in there - your D16A6 had the cooling fan switch on the back of the block right next to the oil filter (big round black rubber boot connector wit 2 wires, one black and one yellow with green stripe) - the D16A should have the cooling fan switch on the thermostat housing - you need to extend the 2 wires to reach the thermostat housing and install a different 2 -wire connector which you can probably get from a salvage yard from any 92-up Civic, Integra, etc. - the alternator on the D16A uses a 4 rib belt - if the engine came with alternator, you are set - if it didn't you can't use the D16A6 alternator (which uses a 3 rib belt) without also using the D16A6 crank pulley - i would stay with the PM6 ECU - you could use the 88-89 Integra PG7, but it may run a little rich - you will also need to use your Si distributor