My old school 340 upgrades and results.

I bought this one from Ed Hamburgers For 340 only back in the 80s...it would be easy to copy...works great two flat pieces of steel with holes for shaft and bolts onto head.....the apparatus for the springs is curved...bad picture here...i modified it years ago to allow to get to springs with car with the engine set back...

I have a piece of pipe that fits over short shaft to compress springs...can do springs on heads in minutes..

just add an air chuck for the cylinder...