Engine -
Before connecting the battery
1. set the timing
2. fill the carburetor
3. oil full, water full?
4. all hose clamps tight
5. spark plug (or any other) wires not resting on the exhaust
6. battery up to full power
7. all electrical connections clean and tight
8. an oil supplement added to the crank case, Comp Cams, sells what
basically used to be GM's Engne Oil Supplement (EOS). Lotsa anti scuff
properties
9. bring the rpm to 2000 or 2500 rpm quickly to break in the cam
shaft, 20 minutes works well

Trans. -
1. oil full, one extra quart full works well
2. drive shaft in place
3. rear wheels off the ground
4. 3 (or so) extra quarts handy
5. funnel handy
6. have a second party handy to keep an eye on and full the trans. as
required.  When the engine starts...it'll suck it up right quick
7. run the trans. thru the gears, check the fluid again

After the initial startup 20 or 30 minutes), shut it down, let it cool
"completely".
Retorque the heads, intake and exhaust manifolds
Check all the fluids

Take it out for a ride.
DO NOT BABY it.  Freeways are the best.  A little crusing, moderatly
hard on the throttle for 1/8th mile or so, cruse a mile or so.  Back
on the throttle fairly hard up to about 75mph.  Do this 6 or 8 times.
Up hill helps during the "throttling" periods too.
Loading the rings like this helps break them in.

This basic method has served me well over the past 30 or so years.
From small block cars to big block cars to motorcycles.

Have fun.

Mike