Will fit into mk1/1.5 and st170 I believe all the mounts etc are the same...only thing that I'm sure wouldn't merge is the flywheel as its for a 1.8 box and the st170 doesn't have the ib5 box.
Not 100% sure on the wiring loom either though since the st170 has cam timing...so my guess would be different loom....or at the very least ecu. St170 not my strong point tbh!
PM me if you like