Help! Wiped cam lobes? - Video inside

Make sure the rocker shafts are oriented right so the oil flows right.

Lube every moving point.

Read up on intake sealing and bolt sealing.

If a bolt ends up missing and you don't know absolutely for a fact that it dropped on the ground or down the exhaust pipe, take it all apart and find it!

The spring variables you mention do exist but are not common, and it does not look to be so for your springs.