Honestly I would go for the complete L67 drive train purchase. Top swaps are risky given that the lower end was never made to handle boost or the harshness of the hole shot from the */C.

Also going with an L67 or L32 (04-09 GP GTP) will allow you to mod the engine further than if you went with a top swap. With proper mods to the */C'd engine you can pull very nice 1/8 and 1/4 times however our biggest enemy is loss of traction on take off so i would also suggest drag bags for you rear end to help stop the car from sitting down and taking the weight off the front tires.

Mine so far has a custom tune, ported Gen3, FWI, 3.4" pulley, 180* T-stat, full FE5 suspension.

this spring it will have a Gen 5, Northstar throttle body, 4" FWI, 3.3"pulley, new tune, headers, and autolite 104'*, S1X cam, 1.61 rockers, 105# valve springs, OE R lifters, anything more and i will be forced to drop the trans again and rebuild it with better parts.

If you have the money I would suggest going with an L32 which has the Gen 5 on it and then upgrade your trans to the HD model. you will want all the hardened parts, 4th gear clutch hub, input shaft and hardened oil pump shaft ( only say pump shaft cause i've already sheard one.) also you may want to add 3.29 gears and V8 chains to the trans build depending on how far you are going to go with it.

Just my .02 cents

Don't forget a high stall torque converter. A very good mod for traction.

Know any good places to just get the entire drivetrain or should I just start searching

u can get a used SC with everything else u need off a SSEi, GTP, LSS, Ultra, ect for a couple hundred dollars from a Junk Yard. Thats the most bang for your buck. but there are things to look for in a used supercharger.
1. Coating coming off of impellers
2. Bearing conditions
3. and steer away from one that has a smaller SC pulley already installed, cause u dont know if they made the correct supporting mods, how hard they were on the car and if routine maintenance was performed.

Oh and a few hundred for a 45hd tranny

If your looking for a supercharger, I have 3 of them sitting on the shelf. All stock in good shape. If you need one ported, let me know, I can do that as well.

How much would u charge to do the porting

I was actually thinking more of a complete drivetrain and not just the supercharger. Engine and tranny, new or used(not too many miles) in running condition. I'm in FL so anywhere around here would be a better bet for me

Much like Sawgunner suggested, I recommend you go with a lower mileage L32 if you can find one. However, search for one from a GTP Competition Group and see if you can get the transmission as well. You will then have 3.29 gears, Gen V, and L32 all in one go.

The lower end on a L36 N/A engine will be able to take the power from a supercharger. It isn't the lower end you will have to worry about if you scan for knock and drop pulleys only with supporting mods and take care of your car. Not sure if I recommend going the route I did though, and just purchasing a GTP. You will not regret it though.

hmmm good info to know. maybe i will have to look harder at the GPs in the yard next time