I went through this same thought process then scored a $400 LS1 and a $100 4L50E trans so my decision became very easy.  Then I dumped about $3K into the LSX with a SLP head/cam/injector package and another $600 or so on the short block for rings, bearings, gaskets, double roller chain and oil pump.  Dropped another $600 in the trans for a 2,800 stall TCI converter and got the internals for free from a buddy for a full rebuild.  
Harness cost about $300 (painless) and I scored the computer on ebay for $120 (new in box as a GM performance PCM).  Found a fellow in Indian that re-programs for $75 plus shipping.  Did the headers on the CHEAP by getting a set of Pacesetter 2000 Z28 non-emission units.  The passenger fit right out of the box.  I also put a Steeroids rack in so I had to move THREE pipes on the driver header.  Topped that off with black ceramic coat and I am good at under $400 for the headers complete.  
Motor mounts from Brewers Performance with stock F body accesory brackets and a custom A/C bracket from Brewers to run the Sanden compressor.  A/C from vintage air.  
Radiator is a 31" x 19" mated to a late model Malibu fan assembly.  The PCM controls the fans neat and clean.
If I had to do this again I believe I would have left the motor more stock as dealing with some idle issues and the excessive (sewing machine) noise that comes from the engine with the head/cam swap is a pain in the butt.  However, when you roll on the throttle is is AMAZING!  
If anybody can do things on the cheap...I can.  This should give a feel for what a DIYer should expect with some eblow grease and creative thinking.
See more on my website:
www.mcspeed.homestead.com
Good luck with your decision!