Bent up stuff

Okay this is my take on this, which is just my opinion. Push rods, I always make them as long as possible with out contacting the bottom of rocker through full sweep.(I found that different makes of adjusters have different lengths from bottom of ball to first thread) Your heads are a copy of the edelbrocks, which are set up for flat tappet cams with up to .575 lift with single springs, so if the heads where not cut for higher lift and dual springs your 1.6 rockers are probably the culprit. You said you did a leak down test and heard no air coming out the intake or exhaust. If you did the leak down properly this to me would rule out valve to piston contact. Two broken springs on same cylinder and bent push rods on both intake and exhaust on most of the cylinders screams valve spring clearance problems to me and if that's the case check your rockers real close because they took the hit from both ends, and if used again will be your next failure point. Pull heads and send them out to a component machine shop and gone through and checked for all clearance problems, make sure you give them the valve lift for the 1.6 rockers and not the 1.5s. New push rods and springs and have shop thoroughly check your rockers and replace if necessary. Just my 2 cents.