Strong short block

Do a big block for that power level and longevity. Otherwise for a stout build... I quoted the key words.
"factory LA short block stroker for the street .... "

- what size stroker ?

Depends on the block available and how good it is.

- what bore ?

As little of a overbore as possible to retain cylinder wall thickness which equals strength.

- Different main caps ?

Just stronger ones, not 4 bolt or I should also say, not to drill the block for 4 bolts.

- girdle ?

I have seen no data on this.

- stud the block ?

Yep

- cam shaft type

Solid roller

- what rotating assembly ?

Forged, top of the line, highest strength available. Look around!

- what year block ?

What ever one sonic checks best. (Thickest in the cylinders.)
Example;
340 block at .030 is great. I would like to avoid more. Sonic check X 3!!!!
4.07 X 4.00 stroke
Or
4.07 X 4.15 stroke

Forged slugs for a pump gas ratio with the head in use.
Oil mods! Pump, passages, rear
main cap oil passage.

Solid roller and fully ported heads with a min. of a 1-3/4 header pipe w/ 3 inch exhaust.

Serious single plane or dual quads.