My 2.8 to '91 305 TBI swap, engine and transmission totally rebuilt and detailed, will cost me around $4,000. Get a better deal on the engine and don't rebuild everything and you could do it "the right way" (otherwise known as "the way everyone usually does it", or the JTR manual way) for about $2500.
I'm at the $4000 mark for just parts alone for the engine swap but this is a rebuilt tranny,rear,and a pretty built 350 and all the external and internal stuff and i still need to lower the truck and have the stuff installed so i'm guessing 6500-7500 when its done but thats a everything done right to the best of my knowledge
Sitting at $5010 including purchase price of truck (V8/TH350 was in but it didn't run woth shit - paid $1000) That includes wasting money on my 1850 carb,and buying - seats, radiator, fans,9" narrowed rear w/locking diff., MSD HEI kit, hoses, belts, slicks,lift bars,drive shaft loop,rebuild heads,new intake,carb,cam,stall converter,windshield,spiral core wires,headers and dual exhaust,tach + gauges and prolly some other crap I can't remember right now. And it still needs body work.
It can depend where you look, or what you want to spend - Built my motor for right around $1000 (I didn't think that was too bad for a 90% stock 2001 LS1) ECU, T56, harnesses and other engine/tranny stuff, about another $1500 - but I also know a guy who runs a shop that deal's strictly with LS1/T56 combos and has a ton of extra parts laying around, so it can help alot as far as budget and expertise with who you know.
Anyway, right now I've spent about $2500 in all for the engine and trannsmission.
I must be on the lucky boat, got a 350 crate motor and a 700r4 combo for 250, bought some head gaskets ($8) swapped out an edelbrock intake ($10) different distributor ($20) Conversion headers ($119) adapter plates ($8). so i am sitting at $415, and i'm pretty close to getting it on the road, just gotta know people i guess.
Heh ill just have someone make my stepdads 94 Transam dissapear (lt1) and tell me where it is, then 2 months later after insurance buys us a new TA ill come home with the engine and axle in the bed of my S-10, say i got it from a junkyard... then find a 6-speed out of a TA (ours is auto) and do the swap with a free, built engine only at 22,000 miles hehe