So this weekend may be firing up the Firebird after a huge swap. What kinda things should be checked before taking it out on the road? Also how much of a easy break in period before going WOT with it?

Here is whats been done:

Swapped from a 91 L03 to a 87 L98 but with a SD harness and ECM from a 91. Rebuilt the heads, many performance upgrades. Cam, Intake work, ect...

Swapped rear from 10 bolt drum to 9 bolt disk 3:45 limited slip, new brakes

Rebuilt Trans

Complete exhaust system

Front Brakes

Added a Line lock

WS6 Wheels / New Tires

AC Deleted, A.I.R. Deleted, Cruise Control Deleted


on a side note cant seem to find the connector for the power steering idle up switch

and with deleting the ac, A.I.R., and cruise control deleted how many extra connectors should I have once everything is plugged in?

 

I just did a similar swap. I basically checked all fluids (engine oil, trans fluid, rear axle, coolant, brake fluid) , primed the oil pump, started the engine, timed engine, let run until fans came on, look for leaks, checked lug nuts and took it for a drive around the block. You didn't state that you made any changes to the reciprocating assembly, and with the 87 you should have a roller cam which don't require any break in period, but I'd recommend driving normal for ~100 miles.