OK Well my exhaust manifold gaskets are shot so i was going to replace them (and port the manifolds while i had them out) this weekend but after I crawled under the car and scouted everything out i realized the front manifold would take me quite a while to get out. I was wondering if i could just do the rear one (closest to the truck) now and wait until i had a couple of days off tho do the other. Would that screw the engine up or anything?

barely. it will run uneven. with a 1-2-3-4-5-6 firing order - thats the exhaust order also, it wont be that noticable - if at all. the unevenness in the fuel/air mix would be well within the uneveness in injector flow.

overall - no - i dont think it would hurt at all. I am thinking exhaust manifold porting is worth 5-10 hp - that is roughly 1 hp per cyl, and just compresion uneveness & injector uneveness are more than thatper cyl

It shouldn't hurt anything. You'll just have one bank of cylinders that exhausts gases easier than the other.

I'll give the above a third.

So for awhile, you'll only have a 3-4 HP gain instead of 6-8 HP.