No on all accounts. If you want AWD, you'll have to get the rare ( less than 1,000 made over 20 years ago) Pontiac 6000 STE with it and work from there. Maybe the turbo variant of the 60 degree V6 out of the rarer ( maybe 300 made) turbo grand prix of the late 80's swapped in. All that for a car with a crappy chassis and a not so good engine. If you want a powerful AWD sedan and don't mind shopping for a while, look for a early 90's Mitsubishi Galant VR4. Forerunner to the EVO as the Mitsu Rally car of choice, it's basically a DSM drivetrain in a Galant Shell. It's basically a bigger version of the EVO II or EVO III which were made off the Mirage ( called the Lancer in Japan) chassis. It'll be cheaper and easier than any of this stuff swapped together into a G body. Plus, the 4G63 takes boost better than the 60 degree GM V6. The only remotely possible "easy" AWD swap into a G body involves modifying the AWD system out of the Astro/Safari vans like GM did when it built the Typhoon/Cyclone super trucks in the early 90's. How? You're on your own there. I considered doing it but rejected it for several technical reasons involving weight distribution, etc. I did figure out some of the technical details of it however, if you are interested.
For a manual trans G body, why use FWD crap? Use the trans out of an F body! As for heads, there was a hybrid 3.8 used in the rare 1989 Trans Am Pace Car replica that involves the 3800 heads on a 3.8 block due to space constraints in the F body chassis, but I am unsure if they were special heads or a special block designed to mate the parts together, or if it's a bolt in. If you really want a 3800 that bad though, use the 3800 Series II V6 out of a 4th Gen F body from the later 90's. It has a RWD T-5 5spd trans and then you have to figure out a clutch linkage. This answers some of the questions you asked. However, the actual post shows somewhat of a lack of knowledge of the basics and I would suggest studying up on them first before trying to build a b*st*rd hybrid. Also, post these things in the right sub forum next time.