340 engine combo ?

[randy73]

I am going to rebuild my 1973 340 and this is what I have come up with.

Crane Hyd. RR - 276/284 112lsa
Crane retro Hyd. RR lifters
Edelbrock 340 RPM heads w/springs for Hyd. RR cam 68cc
PRD Stainless adj. 1.5 RR
KB KB243KTM-030 pistons - Thank Cahllenger 340
going to shave the block .010, according to Edelbrock, I should get 9.6 -9.7:1 compression

Has stock manifolds, but am planning on either TTI or Hooker comp.

Bottom end will be rebuilt stock, except for the .030 over pistons.

Tranny is 95 46rh, with lockup at 38 mph and with vacuum switch and 2100 stall converter
Rearend is a 3:23 SG

Is there any way to figure out how long the pushrods need to be?
would like to buy them in advance, if I can.

Planning on making this car a driver, but probably not a DD, because if the car got wrecked, you would see a grown man ball like a baby.