[tubbedII]

It's always nice to start with a running vehicle...love the 68 nose on a blazer too!

Let me try to help with what you listed:

1 Fuel gauge/tachometer do not work
There should be a wire that's connected to the sender on the tank. Make sure it's all connected and there's good grounds back there. Is the tach aftermarket or stock int he cluster?
2 Gas tank does not fill up properly, I dont think it lets air out when you are filling up and gas pours on the ground.
More than likely your tank isn't properly vented. Is it a stock tank? Many threads on this issue, so take a look at your tank and do a few searches and you should be able to get that taken care of pretty easily.
3 Transmission slips, it doesnt always like to go into reverse and you cant feel it shift into drive.
Ouch...
4 I have the 4wd shifter but dont have the bolt
Don't know anything about the 4wd's, but check the classifieds on the board to see if anyone has what you're looking for. FYI, you have to be a subscribing mbr in order to post a WTB (Want To Buy) ad.
5 The steering gear leaks
Ouch again, but you can pick these up almost anywhere
6 I think the front end needs to be rebuilt, it has a lot of play when youre driving. Guess I will know for sure once I get a new steering gear on there.
I'd go with the box 1st too since it's leaking and then replace what's required.

Good luck with the build!