Bob,
First things first… Is this a vehicle that needs to be smogged and kept street legal? If so, look into the AZ rules to see what you are allowed to do. If not, anything goes.
If you are bound to do a legal swap, I doubt a carbureted (read OEM modified) Vortec will pass, unless the AZ rules are very loose. If you want to keep the cost down and want fuel injection, look into a LM7 Gen III Vortec with the 4L60E. It is a very common powertrain, it is very cheap to buy, and it is dead reliable. If your budget allows and you want an aluminum block, the LM4 or L33 will do, but they had a short production life and are harder to find. BTW, I am assuming you were talking 5.3L for cost reasons.
If you are on a slim budget and source your own engine, call Jesse Bubb at
www.wait4meperformance.com for your harness/reprogramming needs. A lot of folks on
www.ls1tech.com use him and he is also very reasonable in his prices. You’re most likely looking at $320 (that’s what he charges for LS1) tops for both harness and reprogramming with all emissions connectors in place. Just give him your gear ratio and tire size, and you’re good to go. Another source is John at
www.speartech.com, but he is much more expensive.
Keep in mind that you’ll need new driveshafts and possibly gauges. However, by running both the Chevy ECM and the TJ PCM and using the TJ sensors, you can reuse your stock cluster and all your stock gauges will work, except for the tach. Last I heard, Detroit Engineering was working on a solution for that. I am not sure about the fuel pressure for the LM7, but if it is like the LS1 requiring 65 psi, you can either modify your existing fuel pump, use a stock 05-06 TJ one, or an inline Walbro one.
If you want A/C, you’ll have to notch the frame to clear the compressor, or relocate it up high on the passenger side (Corvette style). Of course, natural ventilation (no top, doors, or windows) is much cheaper.
The other choice would be a Hemi swap. A Ram 5.7L Hemi with 545RFE is dirt cheap, it doesn’t require new driveshafts, no tranny to t-case adapter, and you don’t have to buy aftermarket gauges (although you’ll need a 2002+ cluster). You’ll most likely need a 1” BL if you don’t have one, and an 05-06 tank and fuel pump for emissions purposes (NVLD). For harness and ECM, Tony Squire at
www.hotwireauto.com is your guy. He and his son Chris have it down to a science, not the cheapest, but the best. BTW, they also do Chevy harnesses, but hot rod style ones, no emissions.
These are some preliminary thoughts, but to guide you better, it would be nice to know if the vehicle needs to be a registered vehicle, what your goals are for doing this swap (including what equipment you want and what you can do away with), your current specs, and also your budget.