I'm going to use something to markup the bottom side to be able to see what needs to be notched.

 

yes i would highly advise to do that and not like i did and find out the hard way

 

I wonder If I should put some blue rtv around the intake ports and to help seal up the surface just in case.

 

i would thats what i plan on doing

 

With the nnbs intake the idle was perfect the only change was the intake and injector at the same time

 

Well I just ordered all new o-rings and new rope gasket from fast should be here by Friday

 

I nvr had the problem u r guess I got lucky

 

Doesn't the rectangle port of the intake mess up with the cathedral port of the head? Gasket matching 101 that would be a SBC nightmare..

 

so while my truck is down i figured ill install a few things ive been putting off like underdrive crank pulley as well as my low temp 160 degree thermostat.

also goin to buy a NNBS crossover tube that goes infront of the motor between the cylinder heads since i found out the other day at work the nipple is on the pass side and not on the drivers like on the NBS trucks which makes things much easier when installing one of these intakes.

think i might just go ahead and do the 05 up efans since i had to pull the radiator to install the underdrive pulley

 

You should do the 11+ e-fan swap. I have a thread about efans asking the difference between 05 and ls1 fans and TXSZ66AVLANCHE said the11+ fans would work if you had the harness for them. When I did mine I was greener than green about performance upgrades and bought my original size rad (28") instead of upgrading to the 34" rad. But I am looking into getting the parts for the bigger rad, e-fans, and harness. Yeah the flow more cfm's than the 05 fans.