Turning the key on a fresh, built engine, help!

[aaron34gtt]

Car is a r34 gtt, was previously running 255rwkw on an unopened engine with a Garrett gtx2867r and ps2000 + supporting mods before the bottom end went due to oil starvation.

The engine has been rebuilt with the following:

Reconditioned head

Titanium valve springs and retainers

Tomei Poncam type b

Block was acid bathed, bored and honed

Arp head studs

Arp rod bolts

Crank collar fitted

Crank polished

Race bearings

Forged pistons and rods

N1 pump

Restrictors

Mls head gasket

Probably missed a few things but thats mainly it, clearences and balancing were all done by my engine builder and rotating assembly also assembled by him.

It will also be running a haltech flex sensor, should i get my tuner to install it?

This is my first engine build and Im extremely nerveous about turning the key.. what are some things i should do before kicking it over? I will be using a mineral oil with no additives, will also prime the engine and counter rotate it.

Can I start the engine with its current tune? Can it be started breifly to check it actually runs before taking it to my tuner?

Thanks for any help

[KiwiRS4T]

My preference is for the tuner to start it. Should be 90% run in by the time its tuned.